Main Reservoir Of Infection Research Articles

Risk Factors for the Anal and Oral Human Papillomavirus (HPV) Infections among Women with Severe Cervical Lesions: A Prospective Case-Control Study.

The carcinogenicity of HPV infection in the anogenital and oropharyngeal regions is broadly accepted. The aim of the study was to define risk factors for anal and oral HPV infections in high-risk patients with biopsy-proven severe cervical lesions (CIN2+). Altogether immunocompetent 473 females with CIN2+ were categorized into the study group and another 245 women into the control group. The strongest risk factor for anal HPV infection was the presence of cervical HPV infection (p < 0.001). Furthermore, ten or more lifetime sexual partners (p = 0.013), a sexual non-coital contact with the anal area (p < 0.001), and actively practicing anal-penetrative intercourse (p < 0.001) were significantly associated with anal HPV. A history of genital warts in the woman (p = 0.010) and the presence of genital warts in the male partner (p = 0.029) were found statistically significant for the risk of oral HPV infection. Our data suggest that the presence of HPV infection, especially high-risk genotypes, in one anatomical site poses the greatest risk for HPV infection in another anatomical site. The cervix is the main reservoir of infection, but the risk factors for anal and oral HPV infections are dissimilar according to different anatomical distances and more complex routes of transmission.

Phylodynamic Analysis Suggests That Deer Species May Be a True Reservoir for Hepatitis E Virus Genotypes 3 and 4.

Hepatitis E virus (HEV) genotypes 3 and 4 (HEV-3 and HEV-4) cause zoonotic infection in humans, with domestic pigs and wild boars being the main reservoirs of infection. Other than suids, HEV-3 and HEV-4 are found in ruminants, most frequently in deer species. However, it is still debatable, whether HEV infection in deer is a spillover, or indicates a stable virus circulation in these host species. To explore the patterns of HEV-3 and HEV-4 transmission in deer and other host species, we performed a Bayesian analysis of HEV sequences available in GenBank. A total of 27 HEV sequences from different deer species were found in GenBank. Sequences from wild boars collected in the same territories, as well as sequences from all mammals that were most similar to sequences from deer in blast search, were added to the dataset, comprising 617 in total sequences. Due to the presence of partial genomic sequences, they were divided into four subsets (two ORF1 fragments and two ORF2 fragments) and analyzed separately. European HEV-3 sequences and Asian HEV-4 sequences collected from deer species demonstrated two transmission patterns. The first pattern was spillover infection, and the second pattern was deer-to-deer transmission, indicating stable HEV circulation in these species. However, all geographic HEV clusters that contained both deer and swine sequences originated from ancestral swine strains. HEV-3 and HEV-4 transmission patterns in ungulates reconstructed by means of Bayesian analysis indicate that deer species are a true host for HEV. However, wild and domestic swine are often the primary source of infection for ruminants living in the same areas. Complete HEV genomic sequences from different parts of the world are crucial for further understanding the HEV-3 and HEV-4 circulation patterns in wildlife.

КЛИНИКО-ЭПИДЕМИОЛОГИЧЕСКИЕ ПРОЯВЛЕНИЯ КЛЕЩЕ-ВОГО ЭНЦЕФАЛИТА

The authors present the clinical and epidemiological features of the disease of tic-based encephalitis among residents in Belarus. The main reservoirs of in-fection are described. We have demonstrated a clinical case of Central Europe-an tick-borne encephalitis. To solve the set tasks in this research, we used methods of epidemiological diagnostics and statistical research methods. Ac-cording to the results obtained, the incidence of leptospirosis in Belarus for the studied interval (2012–2021) was unevenly distributed over the years. The maximum and minimum indicators differed 1.5 times. The average long-term incidence rate was 1.28 cases per 100 000 population. The analyzed period of time was characterized by a long-term epidemic trend towards an increase in the incidence. The risk group for tick-borne encephalitis was adults (95.0 ± 4.87 %). Most patients with tick-borne encephalitis in 2021 lived in the Moscow and Leninsky districts of Minsk (30.0 ± 10.25 % and 20.0 ± 8.94 %, p &lt; 0.05). The efficiency rate of transmission of the tick-borne encephalitis vi-rus during the bite of a virusophoric tick in 2021 was 1 case of TBE in 54 cas-es of tick bites.

Latest concepts relevant to treatment of digital dermatitis in dairy cattle

Digital dermatitis is one of the most common lesions causing lameness in dairy cattle, also affecting beef cattle and sheep. It is a highly infectious polymicrobial infection, with several species of treponeme implicated. Many treatments appear efficacious and given the animal appears the main reservoir of infection, there are strong arguments for proactive targeted treatment of cows with lesions leading to improved welfare, production and disease control. This article explores the antibacterial treatment options for digital dermatitis and some adjunctive therapies that can improve cure rates. Licensed topical antibiotics generally achieve a good outcome, but non-antibiotic alternatives may be preferable for ethical reasons and for chronic or mild lesions. There is a strong rationale for providing non-steroidal anti-inflammatory drugs to reduce pain and inflammation associated with infections. Optimal bandaging technique is still poorly understood and despite the evidence, opinion remains deeply divided on their use.

ОСОБЕННОСТИ ЭПИДЕМИОЛОГИИ ЛЕПТОСПИРОЗА

The authors present the clinical and epidemiological features of leptospirosis among residents in Belarus. The main reservoirs of infection are described. We have demonstrated a clinical case of severe leptospirosis. To solve the set tasks in this research, we used methods of epidemiological diagnostics and statistical research methods. According to the results obtained, the incidence of leptospirosis in Belarus for the studied interval (2007—2020) was unevenly distributed over the years. The maximum and minimum indicators differed six times. The average long-term incidence rate was 0.25 cases per 100 000 population (95 % CI 0.2—0.3). The analyzed period was characterized by a stable long-term epidemic trend towards a decrease in morbidity. Severe clinical signs of leptospirosis have been associated with L. incterohaemorragiae in a male patient. The highest average annual incidence rates of leptospirosis were noted in the Mogilev and Gomel regions (0.85 %00 and 0.49 %00), and the lowest rates were recorded in the Brest region (0.03 %00).

English

Q fever is a common zoonosis with almost a worldwide distribution caused by Coxiella burnetii. Farm animals and pets are the main reservoirs of infection and transmission to humans is usually via inhalation of contaminated aerosols. Infection in humans is often asymptomatic, but it can manifest as an acute disease (usually a self-limited flu-like illness, pneumonia or hepatitis) or as a chronic form (mainly endocarditis). The aim of this review was to describe epidemiological and clinical features of Q fever in Tunisia. A systematic review of all published studies of Q fever in Tunisia was conducted. Although prevalence of immunoglobulins anti-C. burnetii was high among animals and blood donors, Q fever was rarely reported and frequently misdiagnosed by physicians. &nbsp; Key words: Q fever, Coxiella burnetii, epidemiology, Tunisia.

Leishmaniosis in Rodents Caused by Leishmania infantum: A Review of Studies in the Mediterranean Area.

Leishmaniosis infection begins when a phlebotomine sand fly vector inoculates pathogenic protozoan parasites of the genus Leishmania into a mammalian host. In the case of Leishmania infantum, the domestic dog is considered to be the main parasite reservoir, and canine leishmaniosis (CanL) has a high mortality rate in untreated dogs. Hundreds of cases of human leishmaniosis (HL) are reported in the world each year, the incidence in Europe being relatively low. Leishmaniosis control is primarily focused on the dog, combining methods that prevent sand fly bites and boost host resistance to infection. However, these measures are only partially effective and new solutions need to be found. One of the main factors limiting CanL and HL control is the existence of a sylvatic Leishmania transmission cycle that interacts with the domestic cycle maintained by dogs. It is suspected that the main reservoir of infection in wildlife are rodents, whose expansion and rapid population growth worldwide is increasing the risk of human and zoonotic pathogen transfer. The aim of this review is therefore to analyze reports in the literature that may shed light on the potential role of rodents in the leishmaniosis transmission cycle in the Mediterranean area. Following the general methodology recommended for reviews, six databases (Google Scholar, Ovid, PubMed, Science Direct, Scopus and Web of Science) were explored for the period January 1995 to December 2020. The results extracted from 39 publications that met the established inclusion criteria were analyzed. It was found that 23 species of rodents have been studied in nine countries of the Mediterranean basin. Of the 3,643 specimens studied, 302 tested positive for L. infantum infection by serology, microscopy and/or molecular techniques.

Incidence and geographical distribution of canine leishmaniosis in 2016-2017 in Spain and France.

Leishmania infantum is transmitted by sand flies and causes visceral leishmaniasis (VL) in humans, as well as canine leishmaniosis (CanL) in dogs, the main reservoir of infection in Europe. The infection spread northwards in the last two decades, but case data are scarce, hindering monitoring and evaluation of incidence as is required by European WHO guidelines. We aim to identify the current geographical distribution of CanL incidence in Spain, which has been endemic for CanL, and France, where CanL is emerging. An online survey was conducted among veterinarians in Spain and France questioning CanL incidence in the years 2016-2017. These data were interpolated to estimate incidence in both countries using the geographical analysis ordinary kriging. Two hundred and seventy-three (273) veterinarians from 81 out of 148 French and Spanish districts completed the survey. The mean incidence in veterinary practices was 21 CanL cases per 1000 dogs during the past year, which was higher in Spain (31/1000 dogs/year) than in France (6/1000 dogs/year). Incidence rates were highest in south-eastern Spain, but sporadic cases were found up to the most northern regions of France. Our study confirms the northward spread of CanL in Spain and France, as the incidence rates were higher than reported in previous studies and cases were found in areas formerly considered non-endemic for L. infantum. Monitoring the reservoir of infection in dogs is essential for implementing timely and geographically-targeted interventions to prevent further spread of CanL and VL in Europe.

Seroprevalence of Coxiella burnetii in Dairy Cattle and Camel in Sudan

Background: Coxiella burnetii (C. burnetii) is the causative agent of Q fever, a zoonotic disease that is prevalent worldwide. Domestic and companion animals are the main reservoirs of infection. Humans mainly acquire the infection through inhalation of contaminated aerosols. Objectives: This study was carried out to detect the prevalence of C. burnetii antibodies in dairy cattle sera samples collected in nine states and in camel sera samples in four states in Sudan during May 2015 - March 2016. Methods: A total of 244 cattle sera and 76 camel sera samples were collected and screened for anti- C. burnetii IgG antibodies, using a commercial Q fever antibody ELISA test kit (IDEXX). Results: In dairy cattle, the results indicated an overall 29.92% prevalence of C. burnetii antibodies whereas an overall 64.5% prevalence rate was detected in dairy camel. Conclusions: Our data indicate that C. burnetii is widespread in dairy cattle and camel in Sudan. Both animal and human health workers in Sudan should be aware of the possibility of Q fever infection in animals and humans.

Feasibility of eliminating visceral leishmaniasis from the Indian subcontinent: explorations with a set of deterministic age-structured transmission models

BackgroundVisceral leishmaniasis (VL) is a neglected tropical disease transmitted by sandflies. On the Indian subcontinent (ISC), VL is targeted for elimination as a public health problem by 2017. In the context of VL, the elimination target is defined as an annual VL incidence of <1 per 10,000 capita at (sub-)district level. Interventions focus on vector control, surveillance and on diagnosing and treating VL cases. Many endemic areas have not yet achieved optimal control due to logistical, biological as well as technical challenges. We used mathematical modelling to quantify VL transmission dynamics and predict the feasibility of achieving the VL elimination target with current control strategies under varying assumptions about the reservoir of infection in humans.MethodsWe developed three deterministic age-structured transmission models with different main reservoirs of infection in humans: asymptomatic infections (model 1), reactivation of infection after initial infection (model 2), and post kala-azar dermal leishmaniasis (PKDL; model 3). For each model, we defined four sub-variants based on different assumptions about the duration of immunity and age-patterns in exposure to sandflies. All 12 model sub-variants were fitted to data from the KalaNet study in Bihar (India) and Nepal, and the best sub-variant was selected per model. Predictions were made for optimal and sub-optimal indoor residual spraying (IRS) effectiveness for three different levels of VL endemicity.ResultsStructurally different models explained the KalaNet data equally well. However, the predicted impact of IRS varied substantially between models, such that a conclusion about reaching the VL elimination targets for the ISC heavily depends on assumptions about the main reservoir of infection in humans: asymptomatic cases, recovered (immune) individuals that reactivate, or PKDL cases.ConclusionsAvailable data on the impact of IRS so far suggest one model is probably closest to reality (model 1). According to this model, elimination of VL (incidence of <1 per 10,000) by 2017 is only feasible in low and medium endemic settings with optimal IRS. In highly endemic settings and settings with sub-optimal IRS, additional interventions will be required.Electronic supplementary materialThe online version of this article (doi:10.1186/s13071-016-1292-0) contains supplementary material, which is available to authorized users.

Antimicrobial susceptibility pattern of Methicillin Resistant Staphylococcus Aureus isolated from various clinical samples at SSG hospital, Baroda -

Background: Methicillin resistant Staphylococcus aureus (MRSA) is an important nosocomial pathogen causing significant mortality and morbidity. It is associated with a wide spectrum of infections ranging from mild skin and soft tissue infections to life threatening sepsis. Infected and colonized patients are the main reservoirs of infection and hand carriage by health care workers is the predominant mode of transmission. Aim: This study was undertaken to determine the prevalence of MRSA and their susceptibility pattern at SSG hospital, Baroda. Materials and Methods: 150 isolates of Staphylococcus aureus were obtained from different clinical specimens from hospitalized patients. They were screened for methicillin resistance by standard laboratory procedures. Susceptibility to beta lactams, aminoglycosides, macrolides, fluoroquinolones, glycopeptides and Oxazolidinones were determined by disc diffusion method. Results: Among the 150 Staphylococcus aureus isolates studied, 65 (43.3%) were MRSA. Among the 65 MRSA isolates are 96.93% susceptible to Vancomycin, 100% susceptible to Linezolid and 35.39% susceptible to Gentamicin, 12.31% susceptible to Azithromycin; 32.31% susceptible to Clindamycin and 00% susceptible to penicillin, oxacillin & cefoxitin. Conclusion: The MRSA isolates were associated with a high degree of co-resistance to other groups of antimicrobial agents. Active screening and compliance with recommended infection control practices play an important role in the control of MRSA. Key words: MRSA, Antimicrobial tests, infection control

SEROEPIDEMIOLOGY OF COXIELLOSIS (Q FEVER) IN SHEEP AND GOAT POPULATIONS IN THE NORTHEAST OF IRAN

Summary Coxiella burnetii is the etiological agent of coxiellosis in animals and Q fever (a zoonotic disease) in humans. Cattle, sheep and goats are the main reservoirs of infection for humans. This serological survey was conducted to determine the seroprevalence of coxiellosis in sheep and goat populations in Khorasan Razavi province, Iran. Four hundred and sixty animals (255 sheep from 29 herds in 12 counties and 205 goats from 28 herds in 11 counties) were selected using multi-stage cluster random sampling. Sera were assayed for antibody against C. burnetii using a Q fever ELISA kit. Seroprevalence of C. burnetii at animal level was 36.5% (95% CI: 30.6%-42.4%) for sheep and 29.8% (95% CI: 23.8%-36.2%) for goat populations. The proportion of seropositivity for sheep and goats in the studied counties ranged from 4.5%-72.7% and 6.7%-57.1%, respectively. In 26 (89.6%; 95% CI: 78.6%-100%)�sheep and 22 (78.5%; 95% CI: 63.5%-93.5%) goat flocks, at least one seropositive case was detected. Logistic regression model showed that age and location correlated with seroprevalence of the antibody against C. burnetii at the individual level in both species (P<0.05). There was no difference in seroprevalence between sheep and goat populations (P=0.147). This study showed that a relatively high proportion of animals are seropositive to C. burnetii . Considering the economic and public health importance of C. burnetii in animals and humans, measures are to be implemented to prevent its spreading and to reduce the zoonotic risk of C. burnetii in the studied region.

Field studies on the elimination of footrot in sheep through whole flock treatments with gamithromycin

The main cause of ovine footrot is the anaerobic bacterium Dichelobacter nodosus (Green and George 2008, Winter 2008, Kennan and others 2011). D nodosus is an obligate pathogen of sheep...

Coxiellosis/Q fever in cats: ABCD guidelines on prevention and management.

Q fever is a zoonotic disease caused by Coxiella burnetii. Farm animals and pets are the main reservoirs of infection. Cats become infected by ingestion or inhalation of organisms from contaminated carcases of farm animals, or tick bites. Infection is common, as shown by several serological studies. Experimentally, fever, anorexia and lethargy have been noted. In the field, infection usually remains subclinical. Abortion might occur. C burnetii has been isolated from the placenta of aborting cats, but also from cats experiencing normal parturition. Infection with C burnetii can be diagnosed by isolation of the agent or serology. Most important is the potential zoonotic risk. Cats suspected of having been exposed to C burnetii might shed organisms during parturition. Wearing gloves and a mask when attending parturient or aborting cats can minimise the risk of infection. Tick prevention is recommended.

Hepatitis C virus: the growing challenge

Hepatitis C virus (HCV) is a major cause of liver disease worldwide. In industrialized countries, intravenous drug users (IDUs) are the main reservoir of infection. Relatively little information is available on HCV in the developing world. Peer reviewed publications and presentations at major academic meetings. HCV-related cirrhosis and death from hepatocellular carcinoma are likely to rise dramatically in the next three decades. Urgent intervention is required both to minimize the burden of disease in those already infected and to reduce the incidence of new infections, particularly in the IDU population. Current models of care and commissioning in the UK and other countries do not adequately identify or treat HCV infection in IDUs. Most strategies focus on disease prevention and do not target new infections. New models of care are currently being developed and validated. The development of new models of HCV replication will transform our understanding and capacity to treat HCV infection.

Clinical manifestations of Q fever in adults and children

Q fever is a common zoonosis with almost a worldwide distribution caused by Coxiella burnetii. Farm animals and pets are the main reservoirs of infection and transmission to humans is usually via inhalation of contaminated aerosols, which may be carried by the wind far from the original source of infection. Occupational groups with close association with farm or wild animals are most at risk, however travellers occasionally become infected. The disease is associated with a wide spectrum of clinical manifestations and symptoms, ranging from asymptomatic infection to fatal disease. Awareness of the disease and newer diagnostic methods led to increase of recognition and detection in cases with various or multiple symptoms in adults and children. However, children seem to be less frequently symptomatic and may have milder disease. This review of Q fever cases examines clinical manifestations and symptoms of Q fever in both adults and children and shows that certain symptoms and their severity have altered presentation in children with acute and chronic Q fever when compared to adults.

TaqMan‐Based Detection of Leishmania infantum DNA Using Canine Samples

Leishmaniasis is a typical example of a worldwide diffused zoonosis. Geographic distribution depends on the presence of sand fly vectors and animal reservoirs. In Southern Europe, canines are considered the main reservoir of infection, and the phlebotomines are the vectors. In Sicily, as in all Mediterranean areas, sand flies are present almost all year around because the climate permits an uninterrupted lifecycle for the vectors. Visceral leishmaniasis is becoming a real public health concern especially in endemic areas; in fact, it is an opportunistic infection in immunocompromised patients and in HIV-positive subjects. In Italy, the visceral form of the disease is due exclusively to Leishmania infantum ZMON1, and its prevalence is growing. We have developed a highly accurate, reproducible, and sensible real-time polymerase chain reaction (PCR) assay. In a procedure that used a specific couple of primers, a 117-bp fragment was amplified from minicircle kinetoplast DNA (kDNA). The assay was able to detect even a single parasite (200 fg of DNA). In fact, a single parasite contains hundreds of kinetoplast minicircles for each class. We applied a rapid extraction method coupled with the real-time PCR assay. It was not only as sensitive as a conventional PCR assay for detection of Leishmania kDNA, but also more rapid. The assay is useful for the diagnosis of leishmaniasis in dogs and humans, and it facilitates the monitoring of parasite levels during pharmacological treatment.

Is leishmaniasis becoming endemic in Germany?

Leishmania infantum is transmitted by sand flies and causes visceral leishmaniasis (VL) in humans, as well as canine leishmaniosis (CanL) in dogs, the main reservoir of infection in Europe. The infection spread northwards in the last two decades, but case data are scarce, hindering monitoring and evaluation of incidence as is required by European WHO guidelines. We aim to identify the current geographical distribution of CanL incidence in Spain, which has been endemic for CanL, and France, where CanL is emerging. An online survey was conducted among veterinarians in Spain and France questioning CanL incidence in the years 2016—2017. These data were interpolated to estimate incidence in both countries using the geographical analysis ordinary kriging. Two hundred and seventy-three (273) veterinarians from 81 out of 148 French and Spanish districts completed the survey. The mean incidence in veterinary practices was 21 CanL cases per 1000 dogs during the past year, which was higher in Spain (31/1000 dogs/year) than in France (6/1000 dogs/year). Incidence rates were highest in south-eastern Spain, but sporadic cases were found up to the most northern regions of France. Our study confirms the northward spread of CanL in Spain and France, as the incidence rates were higher than reported in previous studies and cases were found in areas formerly considered non-endemic for L. infantum. Monitoring the reservoir of infection in dogs is essential for implementing timely and geographically-targeted interventions to prevent further spread of CanL and VL in Europe.

Infectious reservoir of Plasmodium infection in Mae Hong Son Province, north-west Thailand

BackgroundIt was unknown whether the main reservoir of Plasmodium falciparum and Plasmodium vivax, which infects mosquitoes in Thailand, was (a) in people feeling sufficiently ill with malaria to come to a clinic or (b) in people who had remained in their home villages with some fever symptoms or with none.MethodsMass surveys were carried out in Thai villages to identify people with Plasmodium infections and with fever. Malaria patients were also located at a clinic which served these villages. Adults from both sources whose blood slides registered positive for Plasmodium spp. were requested to allow laboratory-bred Anopheles minimus to feed on them. Seven to nine days after the blood feeds the mosquitoes were dissected and checked for presence of oocysts.Results and DiscussionThere were higher rates of Plasmodium infection among people in the villages with fever than without fever and much higher rates of infection among clinic patients than among people who had remained in the villages. People with malarial infections identified via the clinic and the village surveys could infect mosquitoes, especially, but not only, if their blood slides showed visible gametocytes. Because only a very small minority of the village populations were visiting the clinic on any one day, assessment indicated that the main reservoir of infection was not primarily among clinic patients but among those in the villages, especially those feeling feverish.ConclusionsEfficient use of an anti-gametocyte drug to suppress the parasite reservoir in a population requires that it be given, not just to clinic patients, but to infected people located by mass surveys of the villages, especially those feeling feverish.

Reply

10 October 2001 Dear Editor REPLY Dr Thies is correct that there are economic arguments against the birth dose of hepatitis B vaccine in Australia, a country of low endemicity. However, these arguments assume that selective vaccination of high-risk neonates is well implemented. An effective control strategy must focus on preventing chronic carriage, as chronic carriers are the main reservoir of infection.1 The risk of carriage is inversely proportional to age, with neonates being at highest risk of becoming carriers.2 A vaccination programme for newborns will have a much greater impact on carriage rates than one at 2 months of age because the risk of chronic carriage is highest (up to 90%) in the neonate. Dr Thies states that he has found ‘no evidence’ of poor implementation of selective programmes, but does not provide any references to support this lack of ‘evidence’. I can only assume he is speaking anecdotally. There are studies from several countries that do provide evidence that vaccination of neonates born to carrier mothers is variably implemented, and that completion of the full schedule of vaccination is poor.3-5 In addition, antenatal screening for hepatitis B, despite the existence of screening policies, is variable.3 Provider factors can have a significant impact on vaccine uptake.3 Although it is quite reasonable (and desirable) to question and evaluate policy, it is unhelpful when providers send mixed messages about national vaccination policy to their patients. The bottom line is that global eradication of hepatitis B cannot be achieved with selective vaccination. The same rationale lies behind the need for continued universal vaccination against poliomyelitis in Australia, despite a very low risk in this country. It is interesting that resistance by health professionals to universal polio vaccination does not seem as prevalent as that towards the hepatitis B vaccine.