Co-infection Patterns Research Articles

Co-infection of blood borne viruses in blood donors: A cross-sectional study from North India

BackgroundThere are several studies on prevalence of individual infectious disease markers (mono-infection) in donors but none on prevalence of coinfection. Co-infection is significant as it leads to accelerated disease progression. We, therefore, evaluated the prevalence of co-infection among blood donors. Materials and methodsThe cross-sectional analysis was conducted in blood donors. All donors were tested for anti-HIV I and II, HBsAg, anti-HBC IgM, anti-HCV, Malaria and syphilis by chemiluminescence and ID-NAT assay. All reactive donor samples were confirmed by using confirmatory assays. Donors were grouped as mono-infected and co-infected. The student t-test was used for comparison. ResultsDuring the study period, a total of 106,238 blood donors were tested. Mean age of donors was 34.2 years and 94.2% of blood donors were males. 1776 (1.67%) donor samples were confirmed serologically reactive. 1714 (1.61%) samples were reactive for single marker (mono-infected) while 62 (0.05%) donors’ samples exhibited co-infection. 18 donors were positive for HBV+HCV followed by HIV +syphilis (14). ConclusionWe report for the first time the prevalence of different co-infection patterns in blood donors. Co-infection influence the disease progression; it would be important to investigate the co-infection prevalence in larger sample size.

Parallel pathogens in the upper and lower respiratory tracts in children with a respiratory tract infection, as revealed by the Filmarray assay

BackgroundRespiratory tract infection (RTI) is a common disease among children of all ages that causes high hospitalization and mortality rates. Infection with more than one pathogen has been reported in RTI; however, the association of the pathogen spectrum in upper and lower respiratory tract infections remains unclear. MethodsA prospective study was conducted during February to October 2016. Fifty-five nasopharyngeal swabs (NPS) and 30 bronchoalveolar lavage fluid (BALF) samples from 55 hospitalized children aged less than 14years (mean age 40months) and diagnosed with an RTI were collected. All samples were detected for 18 respiratory pathogens using the Filmarray assay, real-time PCR, or nested PCR methods. Detection results and clinical characteristics of all cases were analyzed using chi-square and t tests. ResultsForty-one of 55 (74.5%) NPS obtained from children were positive for at least one pathogen by the Filmarray assay. Of these cases, 53.7% (22/41) were co-infected. The most commonly detected pathogen was rhinovirus (RV), followed by Mycoplasma pneumoniae (MP) and respiratory syncytial virus (RSV). Infection by both RV and MP was the most frequently observed pattern of co-infection. Similar results were observed using real-time PCR. The pathogens in the NPS from 76.6% of cases detected by Filmarray and 80.0% of cases by real-time PCR included all the pathogens detected in the BALF sample from the same individual. The Filmarray assay showed an 80% concordance rate with real-time PCR and had a turnaround time of less than 1.2h. No significant differences were observed between the association of single-infection and co-infection with clinical characteristics, neither by Filmarray nor real-time PCR. ConclusionThe spectrum of pathogens is mostly concordant in the upper and lower respiratory tract. Collecting NPS for detection can be a non-invasive and more convenient option compared with BALF. Although co-infection is common in children with an RTI, the clinical significance of co-infection remains unclear and warrants further analysis.

Risk factors associated with sexually transmitted infections among HIV infected men who have sex with men.

To investigate the factors associated with sexually transmitted infection and Human Immunodeficiency Virus (STI-HIV) co-infection among men who have sex with men (MSM). A total of 357 HIV-infected participants (84 STI-HIV co-infection and 273 HIV infections only) were recruited from Jiangsu, China. Logistic regression analyses were used to estimate the related factors associated with STI-HIV co-infection. Marginal structural models were adopted to estimate the effect of transmission drug resistance (TDR) on STI-HIV co-infection. For all participants, logistic regression analyses revealed that those who diagnosed with HIV-1 for longer duration (≥1.8 years) were significantly associated with reduced STI-HIV co-infection risk (OR = 0.55, 95%CI: 0.32–0.96, P = 0.036). In further stratification analysis by antiretroviral therapy (ART), individuals with longer duration showed consistent significant associations with STI-HIV co-infection risk (OR = 0.46, 95%CI: 0.26–0.83, P = 0.010) among MSM with ART-naïve status. In addition, significant reduced risk for STI-HIV co-infection (OR = 0.98, 95%CI: 0.96–0.99, P = 0.010) were observed in younger (under the average age of 31.03) MSM of the same group. Interestingly, we also found TDR was significantly associated with an increased risk of STI-HIV co-infection risk (OR = 3.84, 95%CI: 1.05–14.03, P = 0.042) in ART-naïve group. Our study highlights a pattern of STI-HIV co-infection among MSM in China and indicates that targeted interventions aimed at encouraging TDR monitoring in MSM with early HIV infection are warranted.

Viral coinfection is shaped by host ecology and virus-virus interactions across diverse microbial taxa and environments.

Infection of more than one virus in a host, coinfection, is common across taxa and environments. Viral coinfection can enable genetic exchange, alter the dynamics of infections, and change the course of viral evolution. Yet, a systematic test of the factors explaining variation in viral coinfection across different taxa and environments awaits completion. Here I employ three microbial data sets of virus–host interactions covering cross-infectivity, culture coinfection, and single-cell coinfection (total: 6,564 microbial hosts, 13,103 viruses) to provide a broad, comprehensive picture of the ecological and biological factors shaping viral coinfection. I found evidence that ecology and virus–virus interactions are recurrent factors shaping coinfection patterns. Host ecology was a consistent and strong predictor of coinfection across all three data sets: cross-infectivity, culture coinfection, and single-cell coinfection. Host phylogeny or taxonomy was a less consistent predictor, being weak or absent in the cross-infectivity and single-cell coinfection models, yet it was the strongest predictor in the culture coinfection model. Virus–virus interactions strongly affected coinfection. In the largest test of superinfection exclusion to date, prophage sequences reduced culture coinfection by other prophages, with a weaker effect on extrachromosomal virus coinfection. At the single-cell level, prophage sequences eliminated coinfection. Virus–virus interactions also increased culture coinfection with ssDNA–dsDNA coinfections >2× more likely than ssDNA-only coinfections. The presence of CRISPR spacers was associated with a ∼50% reduction in single-cell coinfection in a marine bacteria, despite the absence of exact spacer matches in any active infection. Collectively, these results suggest the environment bacteria inhabit and the interactions among surrounding viruses are two factors consistently shaping viral coinfection patterns. These findings highlight the role of virus–virus interactions in coinfection with implications for phage therapy, microbiome dynamics, and viral infection treatments.

Influence of Massive and Long Distance Migration on Parasite Epidemiology: Lessons from the Great Wildebeest Migration.

Very little is known about the influence of massive and long distance migration on parasite epidemiology. Migration can simultaneously minimize exposure to common parasites in their habitats and increase exposure to novel pathogens from new environments and habitats encountered during migration, while physiological stress during long distance movement can lead to immune suppression, which makes migrants vulnerable to parasites. In this paper, we investigated the diversity, prevalence, parasite load, co-infection patterns and predilection sites of adult gastrointestinal helminths in 130 migrating wildebeests and tested for their relation with animal age, sex and migration time (which also could indicate different migration routes), and compared them with the non-migratory wildebeest. Surprisingly, only four parasite species were found, Oesophagostomum columbianum, Haemonchus placei, Calicophoron raja and Moniezia expansa, which were lower than in non-migratory wildebeest reported in the literature. These parasites were generalists, infecting livestock, and suggests that wildebeest and livestock, because of their interaction during migration, have a cross-infection risk. There was a negative relation between parasites diversity, prevalence and intensity of infection, and host age, which suggests that wildebeests acquire protective immunity against these parasites as they get older. Prevalence and intensity of infection were higher among wildebeest crossing the Mara Bridge (early migrants) compared to those crossing the Serena (late migrants), which suggests that early migrants (or migrants originating from different areas) have varying infection intensities. The prevalence and intensity of infection were higher in males compared to females and may be due to ecological, behavioural, or physiological differences between males and females. Our findings compared to those of previous studies suggest that migration may provide a mechanism to minimize exposure of hosts to common parasites through migratory escape, but this result awaits examination of helminths epidemiology of non-migratory wildebeests from areas of migrant origins. The potential parasitic cross-infection between wildebeests and livestock is a real risk to be taken into account in the management of wildebeest migration corridors.

Hepatitis C treatment initiation in HIV-HCV coinfected patients.

BackgroundThere are few data regarding HCV treatment initiation among HIV/HCV coinfected patients. The objective of this study was to analyze the changing patterns of HCV coinfection and HCV treatment initiation over time in a large French cohort of HIV/HCV coinfected patients at the beginning of DAA’s era and to analyze factors associated with treatment initiation.MethodsAll HIV/HCV coinfected patients enrolled during 2000–2012 were analyzed. HCV status was defined per calendar year as naïve, spontaneous cure, sustained virological response (SVR), failure or reinfection. HCV treatment initiation rate was determined per year. Trends over time were analyzed using Chi-2 test for trend and linear regression analysis. The effect of covariates on treatment initiation over time was analyzed using generalized estimating equations.ResultsAmong 34,308 HIV-infected patients enrolled between 2000 and 2012, 5,562 were HCV coinfected. HCV prevalence declined from 38.4 to 15.1 %. HCV treatment initiation rate fluctuated from 5.6 to 7.4 %/year from 2000 to 2007, dropped to 5.6 % in 2011 and increased to 8.5 % in 2012 due to the use of first-generation DAAs (29.1 % of initiations in 2012). Cumulative HCV treatment initiation rate increased from 14.8 % in 2000 to 54.7 % in 2012. HCV cure rate increased from 12.4 to 45.2 %. Older age, male gender, male homosexuality, high CD4, undetectable HIV-RNA, CDC stage A-B, and severe fibrosis/cirrhosis were associated with a higher treatment initiation rate. The role of HCV genotype 1, CDC stage, fibrosis and recent HCV infection on treatment initiation rate changed over time.ConclusionA high rate of HCV treatment initiation was observed at the beginning of DAAs era in HIV/HCV coinfected patients. Given the very high efficacy of new DAA-based regimens and if treatment initiation keeps increasing, HCV prevalence among HIV patients will drastically decrease during the forthcoming years.Electronic supplementary materialThe online version of this article (doi:10.1186/s12879-016-1681-1) contains supplementary material, which is available to authorized users.

Pattern of Plasmodium-intestinal helminth co-infection among pregnant women in a high transmission zone of malaria in Nigeria

ObjectiveTo investigate the co-infection of malaria and intestinal helminths and its burden among the pregnant women in Kwara State, Nigeria. MethodsBlood and faecal samples of pregnant women were randomly examined using blood smear and Kato-Katz techniques, respectively. Micro-haematocrit reader was used to estimate packed cell volume (PCV) while information concerning pregnancy and transmission factors was obtained by questionnaire. ResultsOut of the 300 pregnant women, 17.3% had at least one parasite infection and the specific rate of co-infection was 73.1%. Co-infection of Plasmodium falciparum and Ascaris lumbricoides decreased with increasing age while the concurrence of Plasmodium falciparum with hookworm increased with increasing age of women. It was observed that helminth infection protected the severity of malaria and aggravated anaemia level. Pregnant women with malaria alone had average parasitaemia of 1 034.9 parasite/μL of blood and PCV of 30.24% while individuals co-infected with hookworms had parasitaemia of 859.67 parasite/μL and PCV of 26.98%. Our findings also indicated that the prevalence of infection in pregnancy varied with gestation periods. The highest prevalence was recorded in pregnant women in their primigravidae and first trimester. Inadequate toilet facilities, illiteracy, occupations, low incomes and proximities of vegetation around the habitation were observed to influence the transmission of multiple parasites. ConclusionsMass drug administration and maintenance of personal and environmental hygiene are essential preventive measures in endemic communities to ward off the debilitating effects of parasites in pregnancy.

Multiple human papillomavirus infections and type-competition in women from a clinic attendee population in China.

To investigate the multi-infection patterns and type competition for human papillomavirus (HPV) in Chinese clinic attending women and evaluate the association between the infection status and cancer risk. Three hundred and thirty-two HPV-DNA-positive samples were genotyped for 21 HPVs and tested for 13 types of HPV neutralizing antibody using pseudoviron-based assay. Odds ratios (ORs) were calculated to evaluate the coinfection patterns for both DNA and neutralizing antibody (NAb), and the associations of HSIL+ with HPV DNA and NAb. Of the 332 HPV-DNA-positive subjects, 279 (84.0%) were detected as NAb positive. Multi-positive results were identified in 23.2% (77/332) HPV DNA tests and 60.2% (168/279) HPV NAb assays. The NAb titers for the multiple-positive samples (geometric mean 214) were significantly higher than the single-positive samples (geometric mean 114) (P < 0.01). HPV16-HPV52 was identified as a type-competition pair for both HPV DNA (OR = 0.09; 95%CI = 0.02-0.42) and NAb (OR = 0.27; 95%CI = 0.11-0.69) data. Compared to other types, HPV16 DNA was associated significantly with high risk of HSIL+ (OR = 2.57; 95%CI = 1.23-5.38). HPV16-HPV52 was identified as a potential type-competition pair, which might result in the type modulation with the implementation of the approved bi- or quadri-valent vaccines. J. Med. Virol. 88:1989-1998, 2016. © 2016 Wiley Periodicals, Inc.

Co-Infection by Chytrid Fungus and Ranaviruses in Wild and Harvested Frogs in the Tropical Andes.

While global amphibian declines are associated with the spread of Batrachochytrium dendrobatidis (Bd), undetected concurrent co-infection by other pathogens may be little recognized threats to amphibians. Emerging viruses in the genus Ranavirus (Rv) also cause die-offs of amphibians and other ectotherms, but the extent of their distribution globally, or how co-infections with Bd impact amphibians are poorly understood. We provide the first report of Bd and Rv co-infection in South America, and the first report of Rv infections in the amphibian biodiversity hotspot of the Peruvian Andes, where Bd is associated with extinctions. Using these data, we tested the hypothesis that Bd or Rv parasites facilitate co-infection, as assessed by parasite abundance or infection intensity within individual adult frogs. Co-infection occurred in 30% of stream-dwelling frogs; 65% were infected by Bd and 40% by Rv. Among terrestrial, direct-developing Pristimantis frogs 40% were infected by Bd, 35% by Rv, and 20% co-infected. In Telmatobius frogs harvested for the live-trade 49% were co-infected, 92% were infected by Bd, and 53% by Rv. Median Bd and Rv loads were similar in both wild (Bd = 101.2 Ze, Rv = 102.3 viral copies) and harvested frogs (Bd = 103.1 Ze, Rv = 102.7 viral copies). While neither parasite abundance nor infection intensity were associated with co-infection patterns in adults, these data did not include the most susceptible larval and metamorphic life stages. These findings suggest Rv distribution is global and that co-infection among these parasites may be common. These results raise conservation concerns, but greater testing is necessary to determine if parasite interactions increase amphibian vulnerability to secondary infections across differing life stages, and constitute a previously undetected threat to declining populations. Greater surveillance of parasite interactions may increase our capacity to contain and mitigate the impacts of these and other wildlife diseases.

A study on patterns of co-infections among blood donors at the blood bank of a tertiary care referral teaching hospital in South India

Background: Blood serves as a vehicle for transmission of blood-borne pathogens including human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), malaria parasite (MP) and syphilis. Safe blood and blood products should be transfused to all patients in need for blood transfusion. Material and Methods: All blood donors attending to the blood bank during the period January 2009 to December 2014 were screened for hepatitis B surface antigen (HBsAg), anti HCV antibody, anti HIV-1, 2 antibodies and HIV p24 antigen by using the appropriate enzyme-linked immunosorbent assay (ELISA) method and further confirmed using an ELISA kit from a different manufacturer. Malarial antigen testing was done by rapid diagnostic device, which is based on immunochromatographic technique. The rapid plasma reagin (RPR) test was used for estimation of syphilis infection and further confirmed by Treponema pallidum haemagglutination assay (TPHA). Results: Of the 41,785 donors who were screened during the study period, 20 (0.05%) were reactive for different combination of infections. The various combination of infections seen were as follows; HBV+HCV and HBV+HIV (6/20) each, HIV+HCV (3/20), HIV + syphilis (2/20) and HBV+HIV+HCV, HBV+MP, HBV+syphilis (1/20 each); and HIV+Syphilis constituted for 10% (2/20). Conclusion: A properly conducted donor screening, notification and counseling of permanently deferred donors will help in reducing these co-infection rates.

Trypanosoma cruzi and Trypanosoma rangeli co-infection patterns in insect vectors vary across habitat types in a fragmented forest landscape

SUMMARYThe transmission of parasites can be influenced by their co-occurrence with other parasites, in some cases increasing or reducing transmission.Trypanosoma cruzi, aetiologic agent of Chagas disease, often co-occurs withTrypanosoma rangeli, a parasite not pathogenic for mammal hosts. Both parasites can reduce the fitness of their insect vectors (the triatomine bugs; Hemiptera: Reduviidae), withT. rangelibeing more pathogenic for some species. Here, we study the prevalence ofT. cruziandT. rangeliin the triatomineRhodnius pallescensacross a heterogeneously transformed landscape in Panamá. We found that singleT. rangeliinfections were more common in contiguously forested habitats, while singleT. cruziinfections predominated in anthropogenically disturbed habitats.Trypanosoma cruzi–T. rangelico-infections were more common in contiguous forests and in peridomiciliary areas. Furthermore, adult insects were more likely to be co-infected than nymphs. Our results suggest that human-mediated landscape transformation might have increased the predominance of single infections withT. cruziwithin vectors. An important mechanism driving changes in trypanosome infection patterns in triatomines at a landscape scale includes alterations in host species composition that may vary with different degrees of deforestation. Trypanosome co-infection may also confer a survival advantage forR. pallescensto and/or throughout adulthood.

Closing the gap on causal processes of infection risk from cross-sectional data: structural equation models to understand infection and co-infection.

BackgroundEpidemiological studies of disease exposure risk are frequently based on observational, cross-sectional data, and use statistical approaches as crucial tools for formalising causal processes and making predictions of exposure risks. However, an acknowledged limitation of traditional models is that the inferred relationships are correlational, cannot easily distinguish direct from indirect determinants of disease risk, and are often considerable simplifications of complex interrelationships. This may be particularly important when attempting to infer causality in patterns of co-infection through pathogen-facilitation.MethodsWe describe analyses of cross-sectional data using structural equation models (SEMs), a contemporary advancement on traditional regression approaches, based on our study system of feline gammaherpesvirus (FcaGHV1) in domestic cats.ResultsSEMs strongly supported a latent (host phenotype) variable associated with FcaGHV1 exposure and co-infection risk, suggesting these individuals are simply more likely to become infected with multiple pathogens. However, indications of pathogen-covariance (potential facilitation) were also variably detected: potentially among FcaGHV1, Bartonella spp and Mycoplasma spp.ConclusionsOur models suggest multiple exposures are primarily driven by host phenotypic traits, such as aggressive male phenotypes, and secondarily by pathogen-pathogen interactions. The results of this study demonstrate the application of SEMs to understanding epidemiological processes using observational data, and could be used more widely as a complementary tool to understand complex cross-sectional information in a wide variety of disciplines.

Viral Co-Infections in Pediatric Patients Hospitalized with Lower Tract Acute Respiratory Infections.

BackgroundMolecular techniques can often reveal a broader range of pathogens in respiratory infections. We aim to investigate the prevalence and age pattern of viral co-infection in children hospitalized with lower tract acute respiratory infection (LT-ARI), using molecular techniques.MethodsA nested polymerase chain reaction approach was used to detect Influenza (A, B), metapneumovirus, respiratory syncytial virus (RSV), parainfluenza (1–4), rhinovirus, adenovirus (A—F), bocavirus and coronaviruses (NL63, 229E, OC43) in respiratory samples of children with acute respiratory infection prospectively admitted to any of the GENDRES network hospitals between 2011–2013. The results were corroborated in an independent cohort collected in the UK.ResultsA total of 204 and 97 nasopharyngeal samples were collected in the GENDRES and UK cohorts, respectively. In both cohorts, RSV was the most frequent pathogen (52.9% and 36.1% of the cohorts, respectively). Co-infection with multiple viruses was found in 92 samples (45.1%) and 29 samples (29.9%), respectively; this was most frequent in the 12–24 months age group. The most frequently observed co-infection patterns were RSV—Rhinovirus (23 patients, 11.3%, GENDRES cohort) and RSV—bocavirus / bocavirus—influenza (5 patients, 5.2%, UK cohort).ConclusionThe presence of more than one virus in pediatric patients admitted to hospital with LT-ARI is very frequent and seems to peak at 12–24 months of age. The clinical significance of these findings is unclear but should warrant further analysis.

Real-time PCR for detection of Strongyloides stercoralis in human stool samples from Côte d’Ivoire: Diagnostic accuracy, inter-laboratory comparison and patterns of hookworm co-infection

Human infections with the helminth species Strongyloides stercoralis encompass a wide clinical spectrum, ranging from asymptomatic carriage to life-threatening disease. The diagnosis of S. stercoralis is cumbersome and the sensitivity of conventional stool microscopy is low. New molecular tools have been developed to increase sensitivity. We compared the diagnostic accuracy of real-time PCR with microscopy for the detection of S. stercoralis and hookworm in human stool samples, and investigated the inter-laboratory agreement of S. stercoralis-specific real-time PCR in two European laboratories. Stool specimens from 256 randomly selected individuals in rural Côte d’Ivoire were examined using three microscopic techniques (i.e. Kato-Katz, Koga agar plate (KAP) and Baermann (BM)). Additionally, ethanol-fixed stool aliquots were subjected to molecular diagnosis. The prevalence of S. stercoralis and hookworm infection was 21.9% and 52.0%, respectively, whilst co-infections were detected in 35 (13.7%) participants. The diagnostic agreement between real-time PCR and microscopy was excellent when both KAP and BM tested positive for S. stercoralis, but was considerably lower when only one microscopic technique was positive. The sensitivity of KAP, BM and real-time PCR for detection of S. stercoralis as compared to a combination of all diagnostic techniques was 21.4%, 37.5% and 76.8%, respectively. The inter-laboratory agreement of S. stercoralis-specific PCR was substantial (κ=0.63, p<0.001). We conclude that a combination of real-time PCR and stool microscopy shows high accuracy for S. stercoralis diagnosis. Besides high sensitivity, PCR may also enhance specificity by reducing microscopic misdiagnosis of morphologically similar helminth larvae (i.e. hookworm and S. stercoralis) in settings where both helminth species co-exist.

First molecular survey and novel genetic variants’ identification of Anaplasma marginale, A. centrale and A. bovis in cattle from Tunisia

Few data are available about the presence and distribution of Anaplasma species in cattle in North African countries. In this study prevalence, co-infections, risk factors and genetic diversity of Anaplasma species were evaluated in bovines from Northern Tunisia. A total of 232 cattle from 36 randomly selected farms in three Tunisian localities were investigated for the presence of Anaplasma species in blood by Real-time PCR and/or nested PCR. Overall infection rates of Anaplasma spp., Anaplasma marginale, Anaplasma centrale and Anaplasma bovis were 34.9%, 25.4%, 15.1%, and 3.9%, respectively. Anaplasma phagocytophilum was not detected in cattle. The most common co-infection pattern was an association of A. marginale and A. centrale (11.2%). Five cattle (2.1%) all reared in the sub-humid bioclimatic area, were co-infected by the three Anaplasma species. Molecular prevalence of Anaplasma infection varied significantly according to locality, bioclimatic area, tick infestation and type of breeding. Animals of the Holstein breed were less infected by A. marginale and A. centrale than other breeds. Genetic analysis of A. marginale msp4 gene indicated a high sequence diversity of Tunisian strains, suggesting a multiple introduction of infected cattle from different origins. Phylogenetic studies based on the 16S rRNA gene showed that the most prevalent A. centrale strains were closely related to the A. centrale vaccine strain. Moreover, all A. bovis variants clustered with other A. bovis sequences obtained from domestic and wild ruminant strains. This is the first molecular investigation on Anaplasma species in Tunisian cattle providing pivotal background for designing epidemiological studies and to develop control strategies in the country.

Intra-host viral variability in children clinically infected with H1N1 (2009) pandemic influenza

Recent in-depth genetic analyses of influenza A virus samples have revealed patterns of intra-host viral genetic variability in a variety of relevant systems. These have included laboratory infected poultry, horses, pigs, chicken eggs and swine respiratory cells, as well as naturally infected poultry and horses. In humans, next generation sequencing techniques have enabled the study of genetic variability at specific positions of the viral genome. The present study investigated how 454 pyrosequencing could help unravel intra-host genetic diversity patterns on the full-length viral hæmagglutinin and neuraminidase genes from human H1N1 (2009) pandemic influenza clinical cases. This approach revealed unexpected patterns of co-infection in a 3-week old toddler, arising from rapid and complex reassortment phenomena on a local epidemiological scale. It also suggested the possible existence of very low frequency mutants resistant to neuraminidase inhibitors in two untreated patients. As well as revealing patterns of intra-host viral variability, this report highlights technical challenges in the appraisal of scientifically and medically relevant topics such as the natural occurrence of homologous recombination or very low frequency drug-resistant variants in influenza virus populations.

Contaminated open fracture and crush injury: a murine model.

Modern warfare has caused a large number of severe extremity injuries, many of which become infected. In more recent conflicts, a pattern of co-infection with Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus has emerged. We attempted to recreate this pattern in an animal model to evaluate the role of vascularity in contaminated open fractures. Historically, it has been observed that infected bones frequently appear hypovascular, but vascularity in association with bone infection has not been examined in animal models. Adult rats underwent femur fracture and muscle crush injury followed by stabilization and bacterial contamination with A. baumannii complex and methicillin-resistant Staphylococcus aureus. Vascularity and perfusion were assessed by microCT angiography and SPECT scanning, respectively, at 1, 2 and 4 weeks after injury. Quantitative bacterial cultures were also obtained. Multi-bacterial infections were successfully created, with methicillin-resistant S. aureus predominating. There was overall increase in blood flow to injured limbs that was markedly greater in bacteria-inoculated limbs. Vessel volume was greater in the infected group. Quadriceps atrophy was seen in both groups, but was greater in the infected group. In this animal model, infected open fractures had greater perfusion and vascularity than non-infected limbs.

Hepatitis B and C Single and Co-Infection Patterns Among Emergency Patients in a Resource-Limited Setting

Background: Hepatitis B and C viral infections continue to constitute major global health problems and are responsible for most liver related deaths. This study is carried out to reveal the hepatitis B and C single and co-infection patterns among emergency patients and their possible liver outcomes. Methods: Two hundred and eighty-eight (288) patients on initial visit from casualty unit were routinely screened for hepatitis B and C viruses over a period of two years in the haematology department. Diaspot one step enzyme immunoassay rapid kits for hepatitis B surface antigen (HBsAg) and anti-HCV respectively were used. HBsAg and anti-HCV seroprevalence and possible co-infections were evaluated using descriptive statistics of SPSS version 17 and expressed in mean and standard deviation, and male: female ratios. Results: Of the 288 research volunteers, 8.68% and 1.74% were positive for HBsAg and anti-HCV respectively. 1.04% was HBV and HCV co-infected. The overall mean age and male: female ratio were 44.4±17.3 years and 1.4:1 respectively. Lower mean age and higher male: female ratios were observed in HBV and HCV population. HCC remain the major liver outcome in HBV-infected and HBV/HCV co-infected research subjects. Conclusion: Hepatitis B and C viral infections still remain a major public health problem globally. There is need for continued aggressive advocacy on ‘Know your HBV and HCV status’ to reduce the scourge of these infections especially in rural and resource-limited settings where problem of poverty and ignorance have contributed to development of liver complications in these patients.

Pattern of co-infection by enteric pathogenic parasites among HIV sero-positive individuals in a Tertiary Care Hospital, Mumbai, India.

One of the major medical concerns in people living with HIV/AIDS (PLHA) is management of diarrhea that can lead to severe morbidity and mortality. Such clinical scenario warrants an analysis of intestinal parasites, which are important opportunistic pathogens in PLHA. Owing to the scarcity of recent pattern of intestinal opportunistic infections from this region, the study was designed to determine the opportunistic parasites causing diarrhea in PLHA; and to find out whether there is any significant difference in the enteric parasitic pathogens in patients with different immunological status and in those on highly active anti retro-viral therapy (HAART). Analysis of the spectrum of intestinal parasites was carried out with 192 subjects in two groups (142 HIV sero-positive patients having diarrhea and 50 HIV sero-negative patients having diarrhea). The routine light microscopic examination was carried out to determine the infection and CD4+ T-Lymphocyte count was estimated using flow cytometry. Enteric parasites were detected in 35.9% of HIV sero-positive patients having diarrhea and 18% of HIV sero-negative patients having diarrhea. Most common opportunistic enteric parasite was Isospora belli (11.5%); others were Entamoeba histolytica (4.7%), Cryptosporidium sp. (3.6%), Strongyloides stercoralis (3.1%), Giardia intestinalis (3.1%) and Cyclospora cayatanenesis (1.6%). Opportunistic enteric parasites were detected in significantly low numbers in patients with CD4+ T-Lymphocyte counts >500 cells/ml; and in those taking HAART.

Pattern of co-infection by enteric pathogenic parasites among HIV sero-positive individuals in a Tertiary Care Hospital, Mumbai, India

Introduction:One of the major medical concerns in people living with HIV/AIDS (PLHA) is management of diarrhea that can lead to severe morbidity and mortality. Such clinical scenario warrants an analysis of intestinal parasites, which are important opportunistic pathogens in PLHA. Owing to the scarcity of recent pattern of intestinal opportunistic infections from this region, the study was designed to determine the opportunistic parasites causing diarrhea in PLHA; and to find out whether there is any significant difference in the enteric parasitic pathogens in patients with different immunological status and in those on highly active anti retro-viral therapy (HAART).Materials and Methods:Analysis of the spectrum of intestinal parasites was carried out with 192 subjects in two groups (142 HIV sero-positive patients having diarrhea and 50 HIV sero-negative patients having diarrhea). The routine light microscopic examination was carried out to determine the infection and CD4+ T-Lymphocyte count was estimated using flow cytometry.Results:Enteric parasites were detected in 35.9% of HIV sero-positive patients having diarrhea and 18% of HIV sero-negative patients having diarrhea. Most common opportunistic enteric parasite was Isospora belli (11.5%); others were Entamoeba histolytica (4.7%), Cryptosporidium sp. (3.6%), Strongyloides stercoralis (3.1%), Giardia intestinalis (3.1%) and Cyclospora cayatanenesis (1.6%). Opportunistic enteric parasites were detected in significantly low numbers in patients with CD4+ T-Lymphocyte counts >500 cells/ml; and in those taking HAART.