Rotavirus A infection in pre- and post-vaccine period: Risk factors, genotypes distribution by vaccination status and age of children in Nampula Province, Northern Mozambique (2015-2019).

Mozambique introduced the monovalent rotavirus vaccine (Rotarix®, GSK Biologicals, Rixensart, Belgium) in September 2015. Previous analysis, showed that Nampula province continues reporting a high frequency of Rotavirus A (RVA) infection and the emergence of G9P[6], G9P[4] and G3P[4] genotypes. This analysis aimed to determine the RVA frequency; risk factors; genotype distribution by vaccination status and age between pre- and post-vaccine periods in children under-five years old with diarrhea in Nampula. A cross-sectional, hospital-based surveillance study was conducted in the Hospital Central de Nampula in Mozambique. Socio-demographic and clinical data were collected to assess factors related to RVA infection in both periods. Stool specimens were screened to detect RVA by ELISA, and positive samples were genotyped. Between 2015 (pre-vaccine period) and 2016-2019 (post-vaccine period), 614 stool specimens were collected and tested for RVA in which 34.9% (67/192) were positive in pre-vaccine period and 21.8% (92/422) in post-vaccine (p = 0.001). In the post-vaccine period, age, year, and contact with different animal species (chicken, duck, or multiple animals) were associated with RVA infection. RVA infection was higher in children partially vaccinated (40.7%, 11/27) followed by the fully vaccinated (29.3%, 56/191) and the unvaccinated (15.3%, 21/137) (p = 0.002). G1P[8] and G9P[4] were common in vaccinated children less than 12 months. The present analysis showed that RVA infection reduced slightly in the post-vaccine period, with a high proportion of infection and genotype diversity in children, under 12 months of age, vaccinated. Further research on factors associated with RVA infection on vaccinated compared to unvaccinated children and vaccination optimization should be done.

Early impact of rotavirus vaccination in children less than five years of age in Mozambique

Mozambique introduced rotavirus vaccine (Rotarix, GSK Biologicals) in the National Immunization Program in September 2015 with the objective of reducing the burden of total diarrheal disease and specifically severe rotavirus disease. This study aimed to evaluate the early impact of rotavirus vaccine in reducing all-cause diarrhea and rotavirus-specific hospitalizations....

Early impact of rotavirus vaccination in children less than five years of age in Mozambique.

BACKGROUND: Mozambique introduced rotavirus vaccine (Rotarix, GSK Biologicals) in the National Immunization Program in September 2015 with the objective of reducing the burden of total diarrheal disease and specifically severe rotavirus disease. This study aimed to evaluate the early impact of rotavirus vaccine in reducing all-cause diarrhea and rotavirus-specific hospitalizations. METHODS: We analysed stool specimens collected from children under five years old, between January 2014 and June 2017 within the National Surveillance for Acute Diarrhea. We compared annual changes in rotavirus positivity, median age of children hospitalized for rotavirus and the number of all-cause for diarrheal hospitalizations. Rotavirus detection was performed using enzyme immunoassay. RESULTS: During this period, 1296 samples were collected and analyzed. Rotavirus positivity before vaccine introduction was 40.2% (39/97) in 2014 and 38.3% (225/588) in 2015, then after vaccine introduction reduced to 12.2% and 13.5% in 2016 and 2017, respectively. The median age of children hospitalized for rotavirus was 9 and 11 months in 2014 and 2015 and 10 months in 2016 and 2017. Rotavirus hospitalizations exhibited a seasonal peak prior to vaccine introduction, between June and September in 2014 and 2015, coinciding with winter period in Mozambique. After vaccine introduction, the peak was delayed until August to December in 2016 and was substantially diminished. There was a reduction in all-cause acute diarrhea hospitalizations in children aged 0-11 months after vaccine introduction. CONCLUSION: We observed a reduction in rotavirus positivity and in the number of all-cause diarrhea hospitalizations after vaccine introduction. The data suggest rotavirus vaccine is having a positive impact on the control of rotavirus diarrheal disease in Mozambique.

Frequencia e caracterização dos genótipos de rotavirus do grupo A em crianças de 0 a 59 meses de idade, atendidas com diarreeia aguda na pediatria do Hospital Central de Nampula, 2015 / Frequency and characterization of group A rotavirus genotypes in children aged 0 to 59 months, treated with acute diarrhea in the pediatrics of the Hospital Central de Nampula, 2015

A doença diarreica na infância constitui um importante problema de saúde pública em Moçambique. A infecção pelo Rotavirus é a uma das causas mais comum de diarreia aguda grave a nível mundial, sendo a diarreia terceira causa de morbi-mortalidade infantil na maioria dos países em desenvolvimento e considerado responsável por custos elevados de assistência médica e de hospitalização. Na região norte de Moçambique, há pouca informação sobre a contribuição do Rotavirus na etiologia das doenças diarreicas. METODOLOGIA: De Março de 2015 a Fevereiro 2016, foi realizado um estudo descritivo transversal, onde foram incluídas de forma consecutiva crianças dos 0-59 meses, com diarreia aguda internadas nos serviços de pediatria do Hospital Central de Nampula e recolhidas amostras de fezes. Foram igualmente colhidos dados demográficos e clínicos através de um questionário padronizado. A detecção do Rotavirus foi realizada pelo teste ELISA, no laboratório de referência de virologia do INS. As amostras positivas por ELISA foram genotipadas por multiplex transcriptase reversa, reacção em cadeia de polimerase (RT-PCR). RESULTADOS: Das 296 crianças incluidas, o Rotavirus foi detectado em 26.7%, (79/296) sendo 53.2% (42/79) dos positivos do sexo masculino, 73.4% (58/79) dos casos positivos detectados foi na época fria. A distribuição de casos pelas faixas etárias e sua positividade foi a seguinte: 0-6 meses, 11.4% (9/79); 7-12 meses, 50.6% (40/79) sendo 55% masculino e 45% feminino ; 13-24 meses, 32.9% (26/79); 25-36 meses, 3.8% (3/79) e 37-59 meses, 1.3% (1/79). As 79 amostras positivas por ELISA foram genotipadas por multiplex RT-PCR. Nas amostras submetidas a RT-PCR, foram obtidas as seguintes combinações binárias mais frequentes de genótipos 77% G1P[8] , G2P[6] 15% e G9P[4] 5.0 %. CONCLUSÃO: O estudo reporta uma frequência alta de Rotavírus em Nampula. As crianças mais afectadas foram do sexo masculino, na faixa etária de 7-12 meses de idade. O Rotavirus ocorre ao longo do ano com maior frequência no inverno, o genótipo mais frequente foi o G1P[8].

Diarrheal disease in childhood is an important public health problem in Mozambique. Rotavirus infection is one of the most common cause of acute diarrhea worldwide. Diarrhea is the third leading cause of infant morbidity and mortality in most developing countries and responsible for high costs of medical care and hospitalization. In northern Mozambique, there is no information about Rotavirus contribution in the etiology of diarrheal diseases. METHODS: From March 2015 to February 2016, we conducted a cross-sectional study, in which were included consecutively children's for 0-59 months, hospitalized with acute diarrhea at the pediatric services of Nampula Central Hospital. In all children stool samples were collected. There were also collected demographic and clinical data through a standardized questionnaire. The detection of Rotavirus was performed by ELISA at the INS reference virology laboratory. The positive samples in the ELISA test were genotyped by multiplex reverse transcription-polymerase chain reaction RT-PCR. RESULTS: Within 296 included childen's, Rotavirus was detected in 26.7 % (79/296) from which 53.2% (42/79) of the positive cases were male children and 73.4% (58/79) of positive cases detected were detected in winter. The distribution of cases by age groups and their positivity was as follows: 0-6 months, 11.4% (9/79); 7-12 months, 50.6% (40/79) being that male 55% and female 45%; 13-24 months, 32.9% (26/79); 25-36 months, 3.8% (3/79) and 37-59 months, 1.3% (1/79). Those samples Positive in the ELISA test were genotyped by multiplex RT-PCR. From all 79 samples subjected to RT-PCR, Rotavirus genotype G1P[8] was detected in 77 % of samples, G2P[6] in 15% and 5% in G9P[4] . CONCLUSION: This study has shown a high frequency of Rotavirus in Nampula. The most affected children's were male, aged 7-12 months old. Rotavirus was detected in the two seasons more often in the winter and the predominant circulating genotype was G1P [8].