Sentinel Hospital Surveillance Research Articles

Genetic and antigenic characterization of influenza A(H1N1)pdm09 in Yantai, China, during the 2009-2017 influenza season.

This study was performed to determine the antigenic and genetic characteristics and evaluate potential vaccine efficacy of influenza A (H1N1)pdm09 in Yantai from August 2009 to August 2017. A total of 10 236 swabs were collected among patients with an influenza-like illness who were admitted to two sentinel surveillance hospitals in Yantai, East China, from August 2009 to August 2017. All specimens were cultured in Madin-Darby canine kidney cells and identified by haemagglutination-inhibition assay. Complete sequences of haemagglutinin (HA) and neuraminidase of 51 influenza A(H1N1)pdm09 strains circulating in Yantai were amplified, sequenced and analysed using molecular and phylogenetic methods. The potential vaccine efficacy was calculated using the p epitope model which measured the antigenic variation based on the changes in the dominant epitope of HA. The results showed that most Yantai strains were grouped into genetic clades 1.7, 6C, 6B.1 and 6B.2. The amino acid substitutions accumulated gradually in HA proteins and considerable genetic variation were observed in circulating A(H1N1)pdm09 viruses during the seven influenza seasons. The V241I, N369K, N386K and K432E mutations which may change the binding pattern and affinity of oseltamivir for neuraminidase were detected in the strains circulating in 2016/2017 and 2017/2018 seasons and the recommended vaccine strains could afford optimal protection against the influenza A/H1N1pdm09. Although influenza A(H1N1)pdm09 viruses acquired significant genetic variation over the course of seven influenza seasons, the recommended vaccine strains still afforded protection against main circulating strains. Continuous epidemiological and virological surveillance are necessary.

Rotavirus gastroenteritis surveillance in Azerbaijan, 2011–2016

IntroductionRotavirus is a leading cause of acute gastroenteritis and mortality among children worldwide but data describing rotavirus disease in Azerbaijan are lacking. This analysis describes the rotavirus disease burden in Baku, the largest city in Azerbaijan. MethodsWe conducted active, prospective, sentinel hospital surveillance with laboratory confirmation for rotavirus among children under 5 years of age hospitalized at a large pediatric hospital in Baku during 2011–2016. Children with bloody diarrhea, or prior use of antibiotics or intravenous fluids were excluded. The guardians of enrolled children completed a questionnaire documenting clinical and demographic information. A stool specimen was collected from each enrolled child. We report the number and proportion of rotavirus positive hospitalizations during the surveillance period and a clinical description of rotavirus-positive and rotavirus-negative children. ResultsFrom July 2011 through June 2016, 3139 children <5 years of age were enrolled into the surveillance system. Of these, 523 (17%) were positive for rotavirus, varying from 13% to 21% by surveillance year, with a median of 16% over the surveillance period. Increase in rotavirus detections occurred during December-May. Most rotavirus infections (303/523; 58%) occurred in children aged 6–23 months. ConclusionRotavirus is responsible for approximately 16% of annual hospital admissions for acute gastroenteritis in children <5 years of age in Baku. This is lower than regional estimates. Exclusion of children with a history of antibiotic use or intravenous fluids may be accounting for this lower prevalence, and expansion of surveillance to include these groups could provide a more comprehensive picture of acute rotavirus gastroenteritis in Baku.

Epidemiology of acute diarrhea caused by rotavirus in sentinel surveillance sites of Vietnam, 2012–2015

A prospective, multicentre study was conducted in four sentinel surveillance hospitals to assess the trend and epidemiology of acute diarrhea caused by Rotavirus in Vietnam. During the period 2012–2015, a total 8,889 children under 5 years of age were enrolled in the surveillance, and 8689 stool samples were collected. Of these cases, Rotavirus was most common pathogen 46.7% (4054 cases); in which 26.6% (1117) rotavirus-positive stool samples were evaluated to identify genotypes. The proportion of rotavirus positive specimens decreased annually from 54.7% in 2012 to 36.6% in 2015. Rotavirus was detected year-round, but most rotavirus gastroenteritis cases (77.1%) occurred between December and May, corresponding to the rotavirus seasonality. It is found that the peaks varied by regions. Rotavirus positivities varied between the youngest and oldest age, but children 6–11 months old (38.8%) and 12–23 months old (38.4%) counted for most cases. A significant higher number of diarrhea within 24 hours (8.3 times, 95%CI: 8.1–8.4 times) and higher proportion of severe dehydration (12.9%) in Rotavirus positive group than that in Rotavirus negative group (7.7 times, 95%CI: 7.6–7.9 times; and 9.7%, respectively). A downtrend of prevalence of G1P[8] was observed from 82% in 2013 to 15% in 2015. However, G2P[4] was found in 5% of samples in 2012, 9% in 2013, 36% in 2014, and 28% in 2015. Rotavirus infection is the most important cause of acute diarrhea among hospitalized children in Vietnam, and a rotavirus vaccination program for children may significantly reduce this disease.

Incidence of human brucellosis in the Kilimanjaro Region of Tanzania in the periods 2007-2008 and 2012-2014.

BackgroundBrucellosis causes substantial morbidity among humans and their livestock. There are few robust estimates of the incidence of brucellosis in sub-Saharan Africa. Using cases identified through sentinel hospital surveillance and health care utilization data, we estimated the incidence of brucellosis in Moshi Urban and Moshi Rural Districts, Kilimanjaro Region, Tanzania, for the periods 2007–2008 and 2012–2014.MethodsCases were identified among febrile patients at two sentinel hospitals and were defined as having either a 4-fold increase in Brucella microscopic agglutination test titres between acute and convalescent serum or a blood culture positive for Brucella spp. Findings from a health care utilization survey were used to estimate multipliers to account for cases not seen at sentinel hospitals.ResultsOf 585 patients enrolled in the period 2007–2008, 13 (2.2%) had brucellosis. Among 1095 patients enrolled in the period 2012–2014, 32 (2.9%) had brucellosis. We estimated an incidence (range based on sensitivity analysis) of brucellosis of 35 (range 32–93) cases per 100 000 persons annually in the period 2007–2008 and 33 (range 30–89) cases per 100 000 persons annually in the period 2012–2014.ConclusionsWe found a moderate incidence of brucellosis in northern Tanzania, suggesting that the disease is endemic and an important human health problem in this area.

Estimating the burden of influenza-associated hospitalization for cases of severe acute respiratory infection, Beijing, 2015

Objective: To estimate the influenza infection rate among severe acute respiratory infection(SARI) cases and the hospitalization rates of SARI attributable to influenza, based on two sentinel hospital surveillance databases in Beijing, 2015. Methods: Surveillance was conducted at two sentinel hospitals in Beijing in 2015. A total of 1 842 patients who admitted to the sentinel hospitals and met the definition of SARI were enrolled in the study. The respiratory tract specimens of SARI cases were collected, and sent to laboratories within 48 hours for influenza RNA detection. The catchment area of sentinel hospitals was defined by reviewing the home address of inpatients; A total of 1 491 patients were sampled and tested for influenza. The population size of catchment areas was obtained from demographic year book. We investigated the number of pneumonia patients admitted to the sentinel hospitals and other hospitals in catchment areas in 2015, and calculated the proportions of pneumonia patients that were admitted to sentinel hospitals in catchment areas. The catchment population size was calculated using the number of total population of catchment areas multiply by the proportions of pneumonia patients that were admitted at sentinel hospitals. Results: Among 1 491 patients, 13.7% (205 cases) was test positive for influenza viruses, 2 (0.9%) cases positive for influenza A (H1N1), 91 (44.6%) cases influenza A (H3N2), 1 (0.5%) case influenza B/Victoria, 111 (54.0%) cases influenza B/Yamagata. Influenza was associated with an estimated 30 (95%CI:9-51) SARI hospitalizations per 100 000 during 2015. The hospitalization rate was 243 (95%CI: 232-255), 86 (95%CI: 59-112),1(95%CI: 0-5), 8 (95%CI: 0-23) and 92 (95%CI: 16-168) SARI hospitalizations per 100 000 population for<5 years children, 5-14 years children, 15-24 years adult, 25-59 years adult and ≥60 years population, respectively. The hospitalization rate of SARI attributed to influenza A and B was 14 (95%CI:4-17) and 16 (95%CI:0-23) per 100 000 population, respectively. Conclusion: The influenza positive rate among SARI cases was relatively high. The hospitalization burden of SARI attributed to influenza was the greatest in children under 5 year-old.

Respiratory syncytial virus in adults with severe acute respiratory illness in a high HIV prevalence setting

There are limited data on the epidemiology of respiratory syncytial virus (RSV) illness in HIV-infected adults or the elderly in Africa. We studied the epidemiology of RSV-associated severe acute respiratory illness (SARI) hospitalizations in adults in South Africa from 2009 through 2013. Individuals admitted to sentinel surveillance hospitals were investigated by respiratory tract swabs for RSV, using a multiplex real-time polymerase chain reaction assay. The incidence of RSV-associated SARI was calculated for the one site with population denominators. Of 7796 participants investigated, 329 (4%) tested positive for RSV. On multivariable analysis, HIV-infected individuals with RSV-associated SARI had greater odds of being in the age groups 18-44 and 45-64 years (odd ratios (OR) 26.3; 95% confidence interval (CI) 6.2-112.1 and OR 11.4; 95% CI 2.6-50.0) compared with those ≥65 years and being female (OR 2.7; 95% CI 1.4-5.4). The relative risk of hospitalization with RSV-associated SARI was 12-18 times higher in HIV infected individual compared to that of HIV-uninfected. The incidence of RSV-associated SARI was higher in HIV-infected individuals and those aged 65 years and older. Further studies are warranted to describe the disease association of RSV detected in adults with SARI.

Meningococcal Disease in Children in Argentina A 3-year Active Sentinel Hospital Surveillance Study.

Meningococcal disease (MD) is a medical emergency and a serious public health problem. As new meningococcal vaccines become available, MD surveillance is crucial to provide baseline epidemiologic data before implementing preventive measures. We estimated MD incidence and epidemiology in Argentina using hospital-based surveillance. Three-year prospective active surveillance in patients ≤15 years of age was conducted at 6 pediatric hospital sentinel units (March 2012 to February 2015). Of 184,360 hospitalized patients, 1444 (0.78%) had suspected meningitis or MD. Of these, 268 (19%) presented probable acute bacterial meningitis or MD, 168 (63%) were culture positive and 51 (30%) tested positive for Neisseria meningitidis. Of 100 culture-negative cases, 30 had positive meningococcal polymerase chain reaction. Thirteen patients presented other uncommon MD manifestations, resulting in a total of 94 MD cases and an annual incidence of 5.1/10 hospitalized patients [95% confidence interval (CI): 4-6]. Fifty-four (57%) patients were males, 48% were <1 year of age and the median age was 12.5 months (1 month to 15 years). Clinical presentations were the following: meningococcemia and meningitis (37%), meningitis (30%), meningococcemia (16%), arthritis (10%), bacteremia (5%) and pneumonia (2%). Twenty-eight percent had complications. Nine children died (case fatality rate: 10%), and 8 had sequelae. Serogroups were identified for 84 isolates. Serogroup W was associated with age <1 year (odds ratio: 3.18; 95% CI: 1.14-8.99); meningococcemia was associated with mortality (P = 0.0038). Highest rates of MD were observed among young infants. This study provides baseline data to estimate the impact of introducing meningococcal vaccines in Argentina.

Molecular epidemiology of human G2P[4] rotaviruses in Taiwan, 2004–2011

In 2006, two rotavirus vaccines (Rotarix and RotaTeq) became available on the private market in Taiwan. Although vaccine coverage is currently low, molecular surveillance of rotavirus strains can provide pertinent information for evaluation of the potential impact of vaccine introduction and infection control. During January 2008–December 2011, children aged <5years hospitalized with acute gastroenteritis were enrolled from sentinel surveillance hospitals in three geographic areas of Taiwan. Fecal specimens collected from enrolled patients were tested for rotavirus by enzyme immunoassay and reverse transcriptase-polymerase chain reaction. For genotyping, gene specific primer sets were used to amplify and sequence the genes encoding the neutralization antigens, VP7 and VP4. The resulting sequences were then subjected to phylogenetic analysis. In brief, a total of 4,052 fecal specimens were tested and 742 (18%) samples were positive for rotavirus. The annual range of rotavirus positive specimens varied between 16% and 20.7%. Of all specimens, genotype G1P[8] (63.3%) was the predominant strain, followed by G2P[4] (12.5%), G3P[8] (11.7%), and G9P[8] (5.1%). Uncommon strains were also detected in low percentages. We observed that the rotavirus positivity rate steadily decreased from 21% to 16% during 2008–2010, then slightly increased to 20% in 2011, when an increase in the number of G2P[4] cases was observed. Sequence and phylogenetic analysis was carried out to help understand any potential changes of G2P[4] rotaviruses over time. A number of G2P[4] strains collected between 2004 and 2011 were analyzed in detail and our analyses showed marked genetic and antigenic variability in the VP7 and VP4 genes. The Taiwanese strains could be classified into two major G2 VP7 lineages (IV and V) and two major P[4] VP4 lineages (IV and V) and several minor sublineages within lineage IV. Lineage V within both G2 and P[4] represented newly recognized genetic variants of the respective genotypes. The distribution of individual combinations of the G2 and P[4] (sub)lineages showed some temporal variations. This study provides further evidence for the great genetic diversity among G2P[4] strains and helps understand the epidemiological trends of these strains among children in Taiwan.

Risk factors for sporadic Vibrio parahaemolyticus gastroenteritis in east China: a matched case-control study.

SUMMARY To determine risk factors for sporadic Vibrio parahaemolyticus gastroenteritis, we conducted a population-based case-control study in sentinel hospital surveillance areas of Shanghai and Jiangsu province, China. Seventy-one patients with diarrhoea and confirmed V. parahaemolyticus infections were enrolled, and they were matched with 142 controls for gender, age and residential area. From the multivariable analysis, V. parahaemolyticus infections were associated with antibiotics taken during the 4 weeks prior to illness [odds ratio (OR) 7·6, 95% confidence interval (CI) 1·1–54·4)], frequent eating out (OR 3·3, 95% CI 1·0–10·4), and shellfish consumption (OR 3·4, 95% CI 1·0–11·1), with population-attributable fractions of 0·09, 0·24, and 0·14, respectively. Protective factors included keeping the aquatic products refrigerated (OR 0·4, 95% CI 0·2–1·0) and pork consumption (OR 0·2, 95% CI 0·1–0·9) [corrected] .

Efficient surveillance for healthcare-associated infections spreading between hospitals.

Early detection of new or novel variants of nosocomial pathogens is a public health priority. We show that, for healthcare-associated infections that spread between hospitals as a result of patient movements, it is possible to design an effective surveillance system based on a relatively small number of sentinel hospitals. We apply recently developed mathematical models to patient admission data from the national healthcare systems of England and The Netherlands. Relatively short detection times are achieved once 10-20% hospitals are recruited as sentinels and only modest reductions are seen as more hospitals are recruited thereafter. Using a heuristic optimization approach to sentinel selection, the same expected time to detection can be achieved by recruiting approximately half as many hospitals. Our study provides a robust evidence base to underpin the design of an efficient sentinel hospital surveillance system for novel nosocomial pathogens, delivering early detection times for reduced expenditure and effort.

Epidemiology of Respiratory Syncytial Virus-Associated Acute Lower Respiratory Tract Infection Hospitalizations Among HIV-Infected and HIV-Uninfected South African Children, 2010-2011

There are limited data on respiratory syncytial virus (RSV) infection among children in settings with a high prevalence of human immunodeficiency virus (HIV). We studied the epidemiology of RSV-associated acute lower respiratory tract infection (ALRTI) hospitalizations among HIV-infected and HIV-uninfected children in South Africa. Children aged <5 years admitted to sentinel surveillance hospitals with physician-diagnosed neonatal sepsis or ALRTI were enrolled. Nasopharyngeal aspirates were tested by multiplex real-time polymerase chain reaction assays for RSV and other viruses. Associations between possible risk factors and severe outcomes for RSV infection among HIV-infected and uninfected children were examined. The relative risk of hospitalization in HIV-infected and HIV-uninfected children was calculated in 1 site with population denominators. Of 4489 participants, 4293 (96%) were tested for RSV, of whom 1157 (27%) tested positive. With adjustment for age, HIV-infected children had a 3-5-fold increased risk of hospitalization with RSV-associated ALRTI (2010 relative risk, 5.6; [95% confidence interval (CI), 4.5-6.4]; 2011 relative risk, 3.1 [95% CI, 2.6-3.6]). On multivariable analysis, HIV-infected children with RSV-associated ALRTI had higher odds of death (adjusted odds ratio. 31.1; 95% CI, 5.4-179.8) and hospitalization for >5 days (adjusted odds ratio, 4.0; 95% CI, 1.5-10.6) than HIV-uninfected children. HIV-infected children have a higher risk of hospitalization with RSV-associated ALRTI and a poorer outcome than HIV-uninfected children. These children should be targeted for interventions aimed at preventing severe RSV disease.

Progress towards elimination of HIV mother-to-child transmission in the Dominican Republic from 1999 to 2011.

In 1999, prevention of mother-to-child transmission (pMTCT) using antiretrovirals was introduced in the Dominican Republic (DR). Highly active antiretroviral therapy (HAART) was introduced for immunosuppressed persons in 2004 and for pMTCT in 2008. To assess progress towards MTCT elimination, data from requisitions for HIV nucleic acid amplification tests for diagnosis of HIV infection in perinatally exposed infants born in the DR from 1999 to 2011 were analyzed. The MTCT rate was 142/1,274 (11.1%) in 1999–2008 and 12/302 (4.0%) in 2009–2011 (P < .001), with a rate of 154/1,576 (9.8%) for both periods combined. This decline was associated with significant increases in the proportions of women who received prenatal HAART (from 12.3% to 67.9%) and infants who received exclusive formula feeding (from 76.3% to 86.1%) and declines in proportions of women who received no prenatal antiretrovirals (from 31.9% to 12.2%) or received only single-dose nevirapine (from 39.5% to 19.5%). In 2007, over 95% of DR pregnant women received prenatal care, HIV testing, and professionally attended delivery. However, only 58% of women in underserved sugarcane plantation communities (2007) and 76% in HIV sentinel surveillance hospitals (2003–2005) received their HIV test results. HIV-MTCT elimination is feasible but persistent lack of access to critical pMTCT measures must be addressed.

Decline in Rotavirus Hospitalizations and Health Care Visits for Childhood Diarrhea Following Rotavirus Vaccination in El Salvador

A recent postlicensure study from El Salvador showed that the monovalent rotavirus vaccine conferred 76% protection against rotavirus hospitalizations. We further examined the impact of rotavirus vaccination on the national burden of childhood diarrhea to help assess the total public health benefits of vaccination. We compared all-cause diarrhea and rotavirus-specific hospitalization rates during prevaccine year 2006, with postvaccine years 2008 and 2009 in children < 5 years of age from 7 sentinel surveillance hospitals. We also compared annual rates of diarrhea-related healthcare events during prevaccine years 2005 and 2006 with postvaccine years 2008 and 2009 to examine the national burden of healthcare utilization for all-cause diarrhea. Among sentinel surveillance hospitals, rotavirus hospitalization rates among children < 5 years of age declined by 81% (95% confidence interval [CI]: 78%-84%) in 2008 when 2-dose rotavirus vaccine coverage was 50% among infants < 1 year; the decline was 69% (95% CI: 65%-73%) in 2009 when 2-dose vaccine coverage was 61% among infants < 1 year, compared with 2006. The greatest declines were observed in children ≤ 1 year of age, although sizeable reductions were also observed among children ≥ 2 years in 2008. National diarrhea-related healthcare visits during rotavirus season decreased by 48% (95% CI: 47%-48%) in 2008 and by 35% (95% CI: 34%-35%) in 2009 compared with the mean rate from the 2005 and 2006 rotavirus seasons. Rotavirus vaccination had a substantial public health impact on rotavirus disease and overall diarrhea events in El Salvador. Important age-related changes in diarrheal incidence emphasize the need for ongoing rotavirus surveillance after vaccine introduction.

Two Distinct Surveillance Methods to Track Hospitalized Influenza Patients in New York State During the 2009–2010 Influenza Season

To better understand the severity of 2009 H1N1 influenza disease, enhanced surveillance of patients hospitalized with influenza was conducted during the 2009-2010 influenza season in New York State through existing Emerging Infections Program surveillance and a newly established sentinel hospital surveillance program. The 2 surveillance systems were compared to determine consistency across surveillance modalities and reveal the strengths and weaknesses of each to accomplish comprehensive influenza surveillance. Similar variables from the aggregate data collected from each system were compared and differences were analyzed in detail. New York State. Hospitalized adult and pediatric patients detected through 2 influenza surveillance programs. Significant differences in age distribution, timing of illness onset, illness complications, underlying medical conditions, critical care admissions, use of mechanical ventilation, and illness outcomes. Both surveillance systems saw the highest numbers of confirmed influenza infection among patients hospitalized in early fall 2009, with sharp declines thereafter. Sentinel hospital surveillance continued to detect hospitalizations for influenza-like illness that were not due to 2009 H1N1 influenza well into March 2010. Compared to influenza surveillance conducted through the Emerging Infections Program, the sentinel hospital influenza surveillance program tended to detect a sicker population of children and adults, including a higher rate of critical illness and mechanical ventilation, and among adults, higher rates of some underlying medical conditions. There were no differences in disease outcomes detected between the 2 systems. Although the 2 surveillance systems were complementary, inherent methodologic variations revealed important differences at season conclusion. The lessons learned should be used to determine the best way to allocate resources to meet the needs of future state and national influenza surveillance efforts.

The Epidemiology of Rotavirus Diarrhea in Countries in the Eastern Mediterranean Region

Rotavirus is the leading cause of severe diarrhea among children worldwide, killing approximately 600,000 children annually, including 64,800 in the Eastern Mediterranean Region. Safe, effective rotavirus vaccines will be available soon, and accurate disease burden data will be needed to assess the burden of rotavirus and the value of new vaccines and monitor vaccine program impact. To identify epidemiologic studies in which rotavirus diagnostics were applied to children with acute gastroenteritis, we performed a systematic literature review. We selected studies that met 4 criteria and extracted rotavirus data on prevalence estimates, strain identification, age distribution of patients, and seasonal trends. Of the 63 published studies with some rotavirus detection data, 29 met inclusion criteria. Among patients with diarrhea, rotavirus was detected in 40% of inpatients and 23% of outpatients. By 3 years of age, 75% of children experienced a documented rotavirus infection. Circulation of rotavirus occurred year-round, and no clear relationship between the timing of the rotavirus peak with either season or latitude was observed. Comparison of country-specific rotavirus detection rates indicated that the proportion of hospitalizations for rotavirus infection increased with income. This systematic review of studies of rotavirus diarrhea among children in the countries of the Eastern Mediterranean Region documents that rotavirus is one of the most significant causes of childhood diarrhea in the region. The findings of this review will be used to establish sentinel hospital surveillance in these countries, estimate disease burden, and characterize its epidemiology using common protocols and diagnostics.

Etiologic and molecular characteristics of Vibrio parahaemolyticus strains isolated from diarrheal patients in Shenzhen, in 2007 - 2008

To study the infection status and the molecular characteristics of Vibrio parahaemolyticus isolated from diarrheal patients in Shenzhen, in 2007 to 2008 and to provide evidence for the prevention and control of diarrheal diseases caused by Vibrio parahaemolyticus. More than 80 fecal specimens from four sentinel surveillance hospitals were collected and cultured each month. A total of 361 isolates of Vibrio parahaemolyticus were sero-typed and examined by real-time PCR for the presence of two major virulence genes, tdh and trh. Of 361 strains, 60 O3: K6 strains isolated from six suspected outbreaks in August, 2007 and in September, 2008 were typed by pulsed-field gel electrophoresis (PFGE). 4384 stool samples were detected in four sentinel surveillance hospitals and with 361 Vibrio parahaemolyticus strains isolated that belonged to 28 serotypes. Serotype O3:K6, O4:K8 and O1:KUT accounted for 67.90%, 7.50% and 6.10%, respectively. Of 361 strains, 337 strains belonged to tdh+trh-, 11 strains were tdh-trh- and 13 strains were tdh+trh+. The most prevalent serotype which caused diarrheal diseases was tdh+trh in Shenzhen. The 60 isolates were discriminated into twenty different PFGE patterns, which belonged to three clones. Among the 60 isolates, most of the PFGE patterns of isolates from the suspected outbreak locations were identical and some strains isolated from different year were different. Vibrio parahaemolyticus isolates in Shenzhen were dominated by O3:K6 strains. Most of these isolates carried tdh gene and few carried trh gene. Meanwhile, the identical patterns of isolates from 6 suspected outbreaks locations demonstrated that Vibrio parahaemolyticus outbreaks occurred in July 2007 and in September 2008 in Shenzhen. However, the dominated strains' PFGE patterns were different each year, indicating that the sources of Vibrio parahaemolyticus had a multiplex nature and the multiplex sources such as water, sea food and pickled products should be integrated monitored. Laboratory based surveillance of diarrheal diseases could contribute in establishing early warning system for the better prevention and control of diarrheal diseases.

Epidemiology of Rotavirus Gastroenteritis among Children &lt;5 Years of Age in Morocco during 1 Year of Sentinel Hospital Surveillance, June 2006–May 2007

In anticipation of vaccine introduction, we assessed the epidemiology, burden, and genotype of infecting strains of rotavirus disease among Moroccan children hospitalized for acute gastroenteritis. From June 2006 through May 2007, 345 children <5 years of age who had acute gastroenteritis and were admitted to 4 sentinel hospitals in different regions of Morocco were enrolled in this surveillance study, and stool specimens were tested for the presence of rotavirus with use of enzyme immunoassay. RNA from positive samples was genotyped by reverse-transcriptase polymerase chain reaction. Overall, 314 children had complete data available, and among these, 138 (44%) tested positive for rotavirus. Rotavirus infection was most common among children <24 months of age (95% of all hospitalizations for rotavirus infection). Rotavirus infection was detected year-round at all 4 sites but was most prevalent from September through January. Genotype analysis demonstrated that 30.6% of samples were G1[P8], 26% were G9[P8], 7.5% were G2[P6], 3.7% were G1[P6], and 0.7% were G2[P8]. Nucleotide sequencing analysis of G- or P-untypeable strains showed that 4.5% were G9[P8], 2.2% were G1[8], 2.2% were G2[P6], and 1.5% were G2[P4]. A high frequency of mixed infection (21%) was found, of which G1G2[P8] accounted for the majority (16.4%). Rotavirus was responsible for 44% of all hospitalizations for diarrhea among young children at these 4 separate sites in Morocco. These data will help inform a decision on the introduction of rotavirus vaccine in Morocco. Continued and extended surveillance in Morocco will be important to monitor changes in the epidemiology of rotavirus disease and the impact of vaccination after introduction.

Sentinel Hospital Surveillance for Rotavirus in Latin American and Caribbean Countries

The burden of rotavirus disease in the Latin American region has been poorly understood despite the promise of effective vaccines. We describe here the implementation and results of a rotavirus surveillance network in the Latin American and Caribbean region. From 2005 through 2007, stool specimens and epidemiologic information were gathered from children <5 years of age who were hospitalized for acute diarrhea (3 looser-than-normal stools within <24 h) lasting <14 days with use of a standardized generic protocol. Stool samples were tested for rotavirus, and a proportion of detected strains were typed. The proportion of samples positive for rotavirus was applied to World Health Organization diarrhea-related mortality estimates to calculate rotavirus-associated mortality. In 2007, the network comprised 54 sites in 11 countries. During 2006-2007, specimens were collected from 19,817 children; 8141 of these specimens were positive for rotavirus. The median percentage of positive specimens in the country was 31.5% (range, 24%-47%). The risk of death from rotavirus diarrhea by age 5 years was 1 of 2874. Strong rotavirus winter seasonality was apparent, even in tropical Central America. Globally common strains (P[8] G1, P[8] G9, and P[4] G2) accounted for >75% of strains, although unusual strains, including G12, were detected at low levels. As rotavirus vaccines continue to be introduced in Latin America, maintenance of surveillance will provide robust pre-introduction data and a platform for estimating vaccine effectiveness and other measures of impact.

Epidemiology of rotavirus gastroenteritis among children under five years in Morocco during one year of sentinel hospital surveillance, June 2006 to May 2007

Epidemiology of rotavirus gastroenteritis among children under five years in Morocco during one year of sentinel hospital surveillance, June 2006 to May 2007

Incidence, Seasonality, Age Distribution, and Mortality of Pneumococcal Meningitis in Burkina Faso and Togo

Streptococcus pneumoniae causes a substantial proportion of meningitis cases in the African meningitis belt; however, few reports exist to quantify its burden and characteristics. We conducted population-based and sentinel hospital surveillance of acute bacterial meningitis among persons of all ages in Burkina Faso and Togo in 2002-2006. S. pneumoniae and other organisms were identified by culture, polymerase chain reaction, or detection of antigen in cerebrospinal fluid (CSF). Information was collected on 2843 patients with suspected acute bacterial meningitis. CSF specimens were collected from 2689 (95%) of the patients; of these 2689, 463 (17%) had S. pneumoniae identified, 234 (9%) had Haemophilus influenzae type b identified, and 400 (15%) had Neisseria meningitidis identified. Of the 463 cases of S. pneumoniae meningitis, 99 (21%) were aged <1 year, 71 (15%) were aged 1-4 years, 95 (21%) were aged 5-14 years, and 189 (41%) were aged >or=15 years (age was unknown for 9 [2%]). In Burkina Faso, the annual incidence rate of pneumococcal meningitis was 14 cases per 100,000 persons, with annual incidence rates of 77, 33, 10, and 11 cases per 100,000 persons aged <1 year, <5 years, 5-14 years, and >or=15 years, respectively. The case-fatality ratio for S. pneumoniae meningitis was 47% (range for age groups, 44%-52%), and 53% of deaths occurred among those aged >5 years. S. pneumoniae meningitis had an epidemic pattern similar to that of N. meningitidis meningitis. Of 48 isolates tested for serotype, 18 were from children aged <5 years; of these 18, 3 isolates (17%) each were serotypes 1, 2, and 5, and 5 isolates (28%) were serotype 6A. The 7-, 10-, and 13-valent pneumococcal conjugate vaccines would cover 6%, 39%, and 67% of serotypes identified among children aged <5 years, respectively. Of the 30 serotypes identified for patients aged >or=5 years, 18 (60%) were serotype 1, whereas no other serotype constituted >10%. The 7-, 10-, and 13-valent vaccines would cover 7%, 70%, and 77% of serotypes. Epidemic pneumococcal meningitis in the African meningitis belt countries of Burkina Faso and Togo is common, affects all age groups, and is highly lethal. On the basis of a modest number of isolates from a limited area that includes only meningitis cases, 7-valent pneumococcal conjugate vaccine might have only a limited and short-term role. By contrast, the proposed 10- and 13-valent vaccines would cover most of the identified serotypes. To better inform vaccine policy, continued and expanded surveillance is essential to document serotypes associated with pneumonia, changes in serotype distribution across time, and the impact of vaccine after vaccine introduction.