Intent to receive flu vaccine and influenza vaccination coverage among health professionals during 2019, 2020 and 2021 campaigns in Côte d'Ivoire.

Vaccination of healthcare workers against influenza is a crucial strategy to reduce transmission amongst vulnerable populations, facilitate patient uptake of vaccination, and bolster pandemic preparedness. Globally, vaccination coverage of health workers varied from 10 % to 88 %. Understanding health workers' knowledge and acceptance of the influenza vaccine, particularly among physicians, is crucial for the fine-tuning and continued success of influenza vaccination campaigns. We conducted a cross-sectional survey of 472 health workers in Abidjan, Côte d'Ivoire, to inform subsequent subnational and national introductions of influenza vaccine and subsequent campaigns targeting health workers in 2019 (14302), 2020 (14872), and 2021 (24473). Using a purposive sample of university hospitals, general hospitals, rural, and urban health facilities, we interviewed a convenience sample of health workers aged 18 years and older. Physicians had the lowest intention to receive the influenza vaccine (58 %), while nurses (78 %) and midwives (76 %) were the most willing. Across all occupations, intention to receive vaccination increased if the vaccine was offered for free or if recommended by the Ministry of Health. 76 % of respondents believed that the influenza vaccine could prevent illness in health workers. Communication strategies, including about the benefits of influenza vaccination, could raise awareness and acceptance among health workers prior to vaccination campaigns. Influenza vaccination coverage rates between 2019 and 2021 were on par with rates of intention to receive vaccination in the 2018 survey; in 2019, 2020, and 2021, coverage among physicians was 73 %, 73 %, and 52 % and coverage among nurses and midwives was 86 %, 86 %, and 74 % respectively. Improving health workers' knowledge and acceptance of the influenza vaccine, particularly among physicians, is crucial for the continued success of influenza vaccination campaigns.

Progress toward sustainable influenza vaccination in the Lao Peoples' Democratic Republic, 2012-2018.

Despite global recommendations for influenza vaccination of high-risk, target populations, few low and middle-income countries have national influenza vaccination programs. Between 2012 and 2017, Lao PDR planned and conducted a series of activities to develop its national influenza vaccine program as a part of its overall national immunization program. In this paper, we review the underlying strategic planning for this process, and outline the sequence of activities, research studies, partnerships, and policy decisions that were required to build Laos' influenza vaccine program. The successful development and sustainability of the program in Laos offers lessons for other low and middle-income countries interested in initiating or expanding influenza immunization.

Evaluating interest in an influenza A(H5N1) vaccine among laboratory workers who work with highly-pathogenic avian influenza viruses in the United States.

BACKGROUND: Highly pathogenic avian influenza A (HPAI) viruses found in poultry and wild birds occasionally infect humans and can cause serious disease. In 2014, the Advisory Committee on Immunization Practices (ACIP) reviewed data from one licensed ASO3-adjuvanted influenza A(H5N1) vaccine for consideration of use during inter-pandemic periods among persons with occupational exposure. To guide vaccine policy decisions, we conducted a survey of laboratory workers to assess demand for HPAI vaccination. METHODS: We designed an anonymous web survey (EpiInfo 7.0) to collect information on demographics, type of work and time spent with HPAI viruses, and interest in HPAI vaccination. Eligible participants were identified from 42 entities registered with United States Department of Agriculture's Agricultural Select Agent program in 2016 and emailed electronic surveys. Personnel with Biosafety Level 3 enhanced (BSL-3E) laboratory access were surveyed. Descriptive analysis was performed. RESULTS: Overall, 131 responses were received from 33 principal investigators, 26 research scientists, 24 technicians, 15 postdoctoral fellows, 6 students, and 27 others. The estimated response rate was 15% among the laboratory personnel of responding principal investigators. One hundred respondents reported working in a BSL-3E area where HPAI experiments occurred with a mean time of 5.1-11.7 h per week. Overall, 49% were interested in receiving an A(H5N1) vaccine. By role, interest was highest among students (80%) and among those who spent >50% of their time in a BSL-3E area (64%). Most (61%) of those who said they might be or were not interested in vaccine believed it would not provide additional protection to current safety practices. CONCLUSIONS: Half of responding laboratory workers was interested in receiving an influenza A(H5N1) vaccine. HPAI vaccination of laboratory workers at risk of occupational exposure could be used along with existing safety practices to protect this population.

Correction: Temporal Patterns of Influenza A and B in Tropical and Temperate Countries: What Are the Lessons for Influenza Vaccination?

[This corrects the article DOI: 10.1371/journal.pone.0152310.].

Indoor exposure to particulate matter and the incidence of acute lower respiratory infections among children: a birth cohort study in urban Bangladesh.

Approximately half of all children under two years of age in Bangladesh suffer from an acute lower respiratory infection (ALRI) each year. Exposure to indoor biomass smoke has been consistently associated with an increased risk of ALRI in young children. Our aim was to estimate the effect of indoor exposure to particulate matter (PM2.5 ) on the incidence of ALRI among children in a low-income, urban community in Bangladesh. We followed 257 children through two years of age to determine their frequency of ALRI and measured the PM2.5 concentrations in their sleeping space. Poisson regression was used to estimate the association between ALRI and the number of hours per day that PM2.5 concentrations exceeded 100 µg/m(3) , adjusting for known confounders. Each hour that PM2.5 concentrations exceeded 100 µg/m(3) was associated with a 7% increase in incidence of ALRI among children aged 0-11 months (adjusted incidence rate ratio (IRR) 1.07, 95% CI 1.01-1.14), but not in children 12-23 months old (adjusted IRR 1.00, 95% CI 0.92-1.09). Results from this study suggest that reducing indoor PM2.5 exposure could decrease the frequency of ALRI among infants, the children at highest risk of death from these infections.

Rotavirus epidemiology: the Asian Rotavirus Surveillance Network.

Availability of new rotavirus vaccines has highlighted the need to collect local disease and economic burden data to aid decision makers at global, regional and country level. The World Health Organization and the GAVI Alliance recommended that generic protocols be used and that regional surveillance networks be established to collect these data, thereby helping to fast-track the introduction of these new vaccines into developing countries. Nine countries and regions participated in the first phase of the Asian Rotavirus Surveillance Network (ARSN), which collected data over a 2-year period during 2001-2003. Overall 45% of diarrhoea admissions in the region were positive for rotavirus, which was higher than had been anticipated. Significant rotavirus strain diversity was noted during the surveillance period. Data collection for a second phase of the ARSN commenced in 2004 and included a greater proportion of poorer countries that would in future be eligible for funding support for rotavirus immunization from GAVI. Limited economic evaluations in Asia have demonstrated the potential for new rotavirus vaccines to be cost-effective but more local analyses are required. Despite the ARSN's comprehensive data from a mix of developed and developing countries, Asia has lagged the Americas in terms of the introduction of rotavirus vaccines into National Immunization Programmes (NIPs). Lack on rotavirus vaccine efficacy data in Asia, particularly in poorer populations, will have contributed to this delay. Thus ensuring that all global regions are simultaneously involved in the evaluation of new vaccines from the beginning and also encouraging more regional collaborations of Ministry of Health representatives could help to accelerate the introduction of new vaccines into NIPs.

Rotavirus disease in Uzbekistan: cost-effectiveness of a new vaccine.

We evaluated the cost-effectiveness of rotavirus vaccination in Uzbekistan from the healthcare system and societal perspectives. Disease burden was estimated using national statistics on hospitalizations and deaths, and international estimates of under-five mortality. Without vaccination, the risk for rotavirus hospitalization by age 5 is 10 per 1000 children. Rotavirus hospitalizations cost US$ 406,000 annually, of which US$ 360,000 (89%) is for medical expenses and US$ 46,000 (11%) is for non-medical and indirect costs. Rotavirus mortality rate at 0.7 per 1000 derived from national data was three-fold lower than the same rate calculated from international estimates of under-five mortality. Rotavirus vaccination could reduce hospitalizations and deaths by 91% and avert US$ 370,000 in hospitalization costs alone. Vaccination would be cost-effective with vaccine prices in a range of US$ 2-25 per child. However, the cost-effectiveness is greatly influenced by mortality, vaccine price and vaccine efficacy.

Epidemiology and strain characterization of rotavirus diarrhea in Malaysia.

OBJECTIVES: The objectives of the study were to describe the epidemiology and strain characterization of rotavirus (RV), to determine the proportion of hospitalizations for diarrhea attributable to RV among children under 5 years of age, and to estimate the disease burden of RV diarrhea in Malaysia. METHODS: All children 0-59 months of age admitted for acute gastroenteritis to Kuala Lumpur Hospital (KLH) or Hospital Umum Sarawak (HUS) were surveyed. The periods of surveillance were from February 1, 2001 to April 30, 2003 in KLH and April 1, 2001 to March 31, 2003 for HUS. RESULTS: The highest rate of RV-associated diarrhea was among children aged 6-17 months, accounting for 55% of RV-associated diarrhea. There was no seasonality observed in either hospital. P[8]G9 strains were predominant, accounting for 73% of all strains in both hospitals, 80% from KLH and 61% from HUS. There was no mortality. CONCLUSIONS: RV was responsible for 38% of hospitalizations for diarrhea. It was most common in the 6-17 months age group. There was no seasonality observed for RV-associated diarrhea. The most prevalent strain of RV was P[8]G9. The estimated incidence of RV-associated diarrhea was 27 per 10000 population under the age of 5 years per year.

[Rotavirus surveillance data from Kunming Children's Hospital, 1998 - 2001].

OBJECTIVE: To study the epidemiological status on rotavirus diarrhea in Kunming to improve the rotavirus vaccine immunization program. METHODS: A hospital-based sentinel surveillance program for rotavirus was set up among children less than 5 years old with acute diarrhea in Kunming Children's Hospital. Clinical information and fecal specimens were collected and rotavirus were detected by polyacrylamide gel electrophoresis (PAGE) and/or enzyme linked immunosorbent assay (ELISA). Positive specimens were further serotyped or genotyped by ELISA and/or RT-PCR. RESULTS: During the three years of surveillance, 466 specimens were collected. Rotavirus were detected on 246 (52.8%) specimens. 97% of the rotavirus diarrhea cases occurred among children less than 2 years old. There was a peak of admissions for rotavirus diarrhea cases between October and December which accounted for 48% of all the rotavirus hospitalizations each year. Among 204 specimens with G serotyping, the predominant strain was serotype G1 (47.5%) followed by G2 (17.6%), G3 (15.7%), G9 (4.9%) and G4 (1.0%). Mixed infection (2.5%) were rare and 22 specimens (10.8%) remained non-typeable. P genotyping showed P[4], P[8] and P[6] were the most common strains, accounting for 29.3%, 27.6% and 13.8% respectively. P[4]G2 was the most common strain which accounted for 34.1% (14/41) followed by P[8]G1 (29.3%) and P[6]G9 (12.2%). Another 7 uncommon P-G combinations were also identified. CONCLUSION: Rotavirus was the major cause of acute diarrhea in Kunming. An effective rotavirus vaccine for prevention and control of rotavirus diarrhea should be developed.

[Surveillance finding on rotavirus in Changchun children's hospital during July 1998-June 2001].

OBJECTIVE: To establish baseline patterns of rotavirus diarrhea and to describe its epidemiologic features in Changchun city, prior to rotavirus vaccine immunization. METHODS: Hospital-based surveillance was conducted among children under 5 years old with acute diarrhea in Changchun Children's Hospital. Fecal samples were determined to identify rotavirus by PAGE and/or ELISA. G serotypes of rotavirus were identified by ELISA and/or nested RT-PCR. P genotyping were carried out by RT-PCR. All data were computerized and analysed by "Generic Manual on Rotavirus Surveillance" set by CDC in the USA. RESULTS: In total, 2 343 diarrhea cases were screened and 1 211 fecal samples were collected. Rotavirus was detected in 31.0% among outpatients and 52.9% in inpatients. During the peak of the season (November through March), 58.6% of diarrhea was caused by rotavirus among inpatients. 95.0% of rotavirus diarrhea cases occurred among children aged < 2 years. The predominant strain was serotype G1 (82.4%), followed by G2 (5.0%), G3 (3.3%), G4 (0.9%). P genotyping showed that P[8] and P[4] were the most common ones. Nine different P-G combinations were identified, four strains (P[8]G1, P[4]G2, P[8]G3, and P[8]G4) commonly seen worldwide accounted for 75.6% of the total. Taken together with uncommon strains, including the novel types P[4]G4 and P[8]G2, it highlights the extraordinary diversity of rotaviruses circulating in China. CONCLUSION: Rotavirus is the major cause of severe child diarrhea in Changchun. Developing a rotavirus vaccine for prevention of severe disease and reduction of treatment costs seemed to be necessary.

Cytokines as mediators for or effectors against rotavirus disease in children.

Rotavirus is the most common cause of severe gastroenteritis in young children, but the pathogenesis and immunity of this disease are not completely understood. To examine the host response to acute infection, we collected paired serum specimens from 30 children with rotavirus diarrhea and measured the levels of nine cytokines (interleukin-1beta [IL-1beta], IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, gamma interferon [IFN-gamma], and tumor necrosis factor alpha [TNF-alpha]) using a microsphere-based Luminex Flowmetrix system. Patients with acute rotavirus infection had elevated median levels of seven cytokines in serum, and of these, the levels of three (IL-6, IL-10, and IFN-gamma) were significantly (P < 0.05) higher than those in serum from control children without diarrhea. Patients with fever had significantly (P < 0.05) higher levels of IL-6 in serum than control children, and those with fever and more episodes of diarrhea had significantly (P < 0.05) higher levels of TNF-alpha than those without fever and with fewer episodes of diarrhea. We further demonstrated a negative association (P < 0.05) between the levels of IL-2 and the number of stools on the day on which the first blood sample was collected. Finally, patients with vomiting had significantly (P < 0.05) lower levels of IFN-gamma than those without vomiting. Our pilot study provides evidence that the types and magnitudes of cytokine responses to rotavirus infection in children influence or reflect the clinical outcome of disease. These findings suggest that certain cytokines may play an important role in the pathogenesis of and the protection against rotavirus disease in children and, consequently, may provide directions and insights that could prove critical to the prevention or treatment of this important disease.

[Epidemiological study of rotavirus diarrhea in Beijing, China - a hospital-based surveillance from 1998 - 2001].

OBJECTIVE: To provide information on epidemiology of rotavirus infection in Beijing, China. METHODS: An ongoing hospital-based surveillance was conducted among children < 5yr old with acute diarrhea according to WHO generic protocol (CID-98). During a 3-year study (Apr. 1998 to Mar. 2001), a total of 484 stool samples were collected from 1 457 patients, including 275 samples from 1 048 outpatients and 209 samples from 409 inpatients. RESULTS: The overall detection rate of rotavirus infection was 25.4%. Rotavirus was responsible for 27.3% of diarrhea inpatients on a yearly base, and 46.2% during rotavirus season. Two peaks of diarrhea were observed each year, one in the summer (June-Sep.) due to bacterial dysentery (16.7%) and another in fall winter (Oct.-Dec.) due to rotavirus infection (23.0%). The detection rate on rotavirus was the highest in age group of 6 - 11 months (38.2%), followed by 1 - 2 years old (28.5%). Ninety six point eight percentage of children were infected under 3 years of age. The number of deaths, possibly caused by rotavirus diarrhea were accounted for 40% of all diarrhea deaths and 11.1% of the total deaths. Serotyping of 123 rotavirus isolates showed that serotype G1 (55.3%) was predominant, followed by G2 (26.8%), G3 (9.8%), G4 (0.8%), and 10 isolates (8.1%) remained non-typeable. Mixed infections (0.8%) seemed to be rare. CONCLUSION: Rotavirus diarrhea was an important infectious disease among children in Beijing. Safe and effective rotavirus vaccines for the prevention of severe diarrheas and the reduction of treatment costs are of significant importance to China.

Safety and immunogenicity of tetravalent rhesus-based rotavirus vaccine in Bangladesh.

BACKGROUND: Rotavirus is the most common cause of severe gastroenteritis among children worldwide. OBJECTIVES: To compare the safety, immunogenicity and shedding patterns of rhesus rotavirus (RRV)-tetravalent vaccine vs. placebo among infants in rural Bangladesh. METHODS: A double blinded, placebo-controlled trial was conducted in which infants (n = 120) were randomly assigned to receive three doses of either vaccine or placebo administered at approximately 6, 10 and 14 weeks of age together with routine immunizations. Data on possible adverse effects of vaccinations were collected daily for 7 days after each dose. Stool samples were collected after each dose, and serum samples were obtained before the first and after the third vaccination. RESULTS: Fever (> or = 38 degrees C), as measured by study assistants, was noted more frequently among vaccinees (15%) than among placebo recipients (2%) during the 7 days after vaccination but was not reported more frequently by parents of vaccinees vs. placebo recipients. Overall 87% of vaccinees had an antibody response (measured by IgA or anti-RRV-neutralizing antibodies) after vaccination compared with 32% of placebo recipients. Rates of seroconversion were higher among subjects with lower levels of prevaccination antibodies and those who shed rotavirus after vaccination. Vaccine strain viruses were detected in stools from placebo vaccine recipients who had evidence of IgA seroconversion. CONCLUSIONS: In this population RRV-tetravalent vaccine was comparably immunogenic and safe as in trials conducted in developed countries, where this vaccine has been proved effective in preventing severe rotavirus diarrhea. These data support continued evaluation of rotavirus vaccines in developing countries.

Multistate outbreak of Norwalk-like virus gastroenteritis associated with a common caterer.

In February 2000, an outbreak of gastroenteritis occurred among employees of a car dealership in New York. The same meal was also supplied to 52 dealerships nationwide, and 13 states reported illness at dealerships where the banquet was served. A retrospective cohort study was conducted to identify risk factors associated with the illness. Stool samples were collected to detect Norwalk-like virus, and sera were drawn and tested for immunoglobulin A antibodies to the outbreak strain. By univariate analysis, illness was significantly associated with consumption of any of four salads served at the banquet (relative risk = 3.8, 95% confidence interval: 2.5, 5.6). Norwalk-like virus was detected by reverse transcription-polymerase chain reaction assay in 32 of 59 stool samples from eight states. Nucleotide sequences of a 213-base pair fragment from 16 stool specimens collected from cases in eight states were identical, confirming a common source outbreak. Two of 15 workers at caterer A had elevated immunoglobulin A titers to an antigenically related Norwalk-like virus strain. This study highlights the value of molecular techniques to complement classic epidemiologic methods in outbreak investigations and underscores the critical role of food handlers in the spread of foodborne disease associated with Norwalk-like virus.

Gastroenteritis viruses: an overview.

Acute gastroenteritis is among the most common illnesses of humankind, and its associated morbidity and mortality are greatest among those at the extremes of age, children and the elderly. In developing countries, gastroenteritis is a common cause of death in children < 5 years that can be linked to a wide variety of pathogens. In developed countries, while deaths from diarrhoea are less common, much illness leads to hospitalization or doctor visits. Much of the gastroenteritis in children is caused by viruses belonging to four distinct families--rotaviruses, caliciviruses, astroviruses and adenoviruses. Other viruses, such as the toroviruses, picobirnaviruses, picornavirus (the Aichi virus), and enterovirus 22, may play a role as well. Viral gastroenteritis occurs with two epidemiologic patterns, diarrhoea that is endemic in children and outbreaks that affect people of all ages. Viral diarrhoea in children is caused by group A rotaviruses, enteric adenoviruses, astroviruses and the caliciviruses; the illness affects all children worldwide in the first few years of life regardless of their level of hygiene, quality of water, food or sanitation, or type of behaviour. For all but perhaps the caliciviruses, these infections provide immunity from severe disease upon reinfection. Epidemic viral diarrhoea is caused primarily by the Norwalk-like virus genus of the caliciviruses. These viruses affect people of all ages, are often transmitted by faecally contaminated food or water, and are therefore subject to control by public health measures. The tremendous antigenic diversity of caliciviruses and short-lived immunity to infection permit repeated episodes throughout life. In the past decade, the molecular characterization of many of these gastroenteritis viruses has led to advances both in our understanding of the pathogens themselves and in development of a new generation of diagnostics. Application of these more sensitive methods to detect and characterize individual agents is just beginning, but has already opened up new avenues to reassess their disease burden, examine their molecular epidemiology, and consider new directions for their prevention and control through vaccination, improvements in food and water quality and sanitary practices.

Rotavirus vaccine and intussusception. Where do we go from here?

Since the discovery of rotavirus in 1973, vaccine technology has moved from the use of monovalent attenuated animal rotavirus strains to the development of multivalent human-animal reassortment vaccines. The first licensed vaccine, a rhesus-human tetravalent vaccine, was licensed in 1998. This vaccine was withdrawn from the market a year later when it was noted that administration of vaccine was associated with an increased risk of intussusception. The future of rotavirus vaccine is dependent on the reasons for this association that have yet to be discovered.

Cost of diarrhea-associated hospitalizations and outpatient visits in an insured population of young children in the United States.

OBJECTIVE: To assess the financial and clinical burden of diarrhea- and rotavirus-associated disease among a population of privately insured US children. METHODS: For the period 1993 through 1996, we analyzed medical claims data from a large, administrative database containing information on approximately 300,000 children <5 years of age to examine trends in, and costs associated, with hospitalizations and outpatient visits for diarrhea. RESULTS: An annual average of 1,186 diarrhea-associated hospitalizations (35 per 10,000 children <5 years) and 33 386 outpatient visits (943 per 10,000 children <5 years) were reported, accounting for 4% of all hospitalizations and 2% of all outpatient visits among children <5 years of age. Diarrhea-associated hospitalizations and outpatient visits showed a distinct winter-spring peak consistent with that of rotavirus infection. The excess of diarrhea-associated events occurring during the winter-spring peak accounted for an average of 50% of all diarrhea-associated hospitalizations and 18% of all diarrhea-associated outpatient visits. The median cost (in 1998 constant dollars) of a diarrhea-associated hospitalization was $2,307, and that for a rotavirus-associated hospitalization was $2,303. Median costs of diarrhea- and rotavirus-associated outpatient visits were $47 and $57, respectively. CONCLUSIONS: Diarrhea is an important cause of morbidity in this insured population of young children. The epidemiologic features of diarrhea-associated events suggest that rotavirus is an important contributor to the overall morbidity from diarrhea. These disease burden and cost estimates should provide useful information with which to assess the costs and benefits of future interventions for rotavirus-associated illness.

"Norwalk-like viruses". Public health consequences and outbreak management.

"Norwalk-like viruses" (NLVs) cause outbreaks of gastroenteritis and are spread frequently through contaminated food or water. Molecular diagnostics now enables detecting viruses in clinical and environmental specimens, linking of NLV strains causing outbreaks in multiple geographic locations, and tracing them to their sources in contaminated food or water. This report reviews recent advances in NLV detection and provides guidelines and recommendations for investigating NLV-related outbreaks, including specimen collection and disease prevention and control. This report also updates information provided in CDC's previously published, Viral Agents of Gastroenteritis: Public Health Importance and Outbreak Management (MMWR 1990;39 [No. RR-5]: 1-24). These CDC recommendations are intended for public health professionals who investigate outbreaks of acute gastroenteritis but could be useful in academic and research settings as well.