Effectiveness of rotavirus vaccine in the prevention of diarrhoeal diseases among children under age five years in Kavango East and West Regions, Namibia

BACKGROUND: Diarrheal diseases due to rotavirus infection contribute greatly to morbidity and mortality rates of babies and young children in many developing countries. This public health concern can effectively be reduced by the use of the rotavirus vaccine, though there is an anecdotal evidence indicating that despite introduction of the vaccine the number of cases of diarrhoea diseases are still high in Namibia, particularly in Kavango east and west regions. OBJECTIVE: This study evaluated the effectiveness of the rotavirus vaccine in preventing diarrhoea cases among children under age five years in Kavango regions. METHODS: The study employed a quasiexperimental design comparing diarrhoea cases before (2010-2013) and after (2014-2017) introduction of the rotavirus vaccine among children under age five years. Data were extracted from District Health Information System version 2 and analysed by using one way analysis of covariance. RESULTS: Before introduction of the rotavirus vaccine, there were 14 500 diarrhoea cases, which is 1.6% rate of infection. After introduction of the rotavirus vaccine, there were 14 400 diarrhoea cases, which is 1.58% rate of infection. This is supported by the effect size (partial eta(2)) of 0.01%, which is very small. The trend of diarrhoea cases after rotavirus vaccine introduction fluctuated with no major decline of diarrhoea cases. CONCLUSIONS: The study concluded that rotavirus vaccine is less effective in preventing diarrhoea diseases among children under age five years in the Kavango regions. Further research is needed to substantiate these findings as other factors can contribute to fluctuation of diarrhoea cases.