Abstract:
Diarrhea and dehydration has been reported to be among the top causes of hospitalization and
mortality in children aged under 5 years. Most cases of diarrhea in childhood are caused by
rotavirus and routine introduction of rotavirus vaccine has been promoted to potentially
reduce incidence and severity of diarrhea and dehydration in vaccinated infants. I examined
changes in admissions of all clinical cases of diarrhea and dehydration following introduction
of routine vaccination with rotavirus vaccine in 2014 in Kenya. Previously studies have
mostly examined changes in admissions with stools positive for rotavirus. This study assessed
changes in admissions due to all-cause diarrhea and dehydration without considering whether
the patient was tested for rotavirus or not.
This was a retrospective observational study that used data from 13 public hospitals currently
involved in a clinical network (Clinical Information Network (CIN)) set up to ensure
improved collection of routine data to improve inpatient care in Kenya. The hospitals were
purposefully selected by the ministry of health to represent different geographical locations in
Kenya. I included data for children aged 2-36 months, the age most vulnerable to rotavirus
infection. Simulations were used to determine whether the sample size yielded enough power
to detect changes in admissions to diarrhea and dehydration. I used interrupted time series
analysis model following a negative binomial distribution to assess changes in the burden of
diarrhea and dehydration. I used 3 pairs of Fourier terms to account for seasonality of
infectious diarrhea admissions. Non febrile admissions (surgical or burns) were used as
controls There were 29,231 patients who were classified to be having diarrhoea as well as
dehydration. The average DAD admissions per month before the vaccine was introduced
(July 2014) was 35 (standard deviation (SD): ±22) and 17 (SD: ±12) after vaccine
introduction. Fitting a Segmented regression analysis model revealed a 28.32% (95% C.I,
0.786 to 0.950) decrease in hospital admissions immediately after July 2014 when the vaccine
was introduced to the Kenya routine childhood immunization program. This was followed by
a 3.00% (95% C.I, 0.786 to 0.950) decrease in month to month hospital admissions due to allcause diarrhea and dehydration after vaccine introduction. There was statistically significant
change in admissions from non-febrile admissions before and after vaccine introduction. In
conclusion, the introduction of the rotavirus vaccine resulted in a reduction in public hospital
admissions because of all-cause diarrhoea and dehydration. It is therefore recommended that
continuous monitoring be done to ensure that its performance over time is known.
