A long-term observational study of paediatric snakebite in Kilifi County, south-east Kenya

Abstract

Introduction Estimates suggest that one-third of snakebite cases in sub-Saharan Africa affect children. Despite children being at a greater risk of disability and death, there are limited published data. This study has determined the: population-incidence and mortality rate of hospital-attended paediatric snakebite; clinical syndromes of snakebite envenoming; and predictors of severe local tissue damage. Methods All children presenting to Kilifi County Hospital, Kenya with snakebite were identified through the Kilifi Health and Demographic Surveillance System (KHDSS). Cases were prospectively registered, admitted for at least 24-hours, and managed on a paediatric high dependency unit (HDU). Households within the KHDSS study area have been included in 4-monthly surveillance and verbal autopsy, enabling calculation of population-incidence and mortality. Predictors of severe local tissue damage were identified using a multivariate logistic regression analysis. Results Between 2003 and 2021, there were 19,606 admissions to the paediatric HDU, of which 584 were due to snakebite. Amongst young children (≤5-years age) the population-incidence of hospital-attended snakebite was 11.3/100,000 person-years; for children aged 6–12 years this was 29.1/100,000 person-years. Incidence remained consistent over the study period despite the population size increasing (98,967 person-years in 2006; and 153,453 person-years in 2021). Most cases had local envenoming alone, but there were five snakebite associated deaths. Low haemoglobin; raised white blood cell count; low serum sodium; high systolic blood pressure; and an upper limb bite-site were independently associated with the development of severe local tissue damage. Conclusion There is a substantial burden of disease due to paediatric snakebite, and the annual number of cases has increased in-line with population growth. The mortality rate was low, which may reflect the species causing snakebite in this region. The identification of independent predictors of severe local tissue damage can help to inform future research to better understand the pathophysiology of this important complication.

Clinical Risk Factors Associated with Poor Outcomes in Snake Envenoming: A Narrative Review

“…Children pose unique clinical challenges to clinicians treating SBE. In rural areas, children have a heightened propensity for snake encounters, as evidenced by the prevalence of up to one-third of reported cases in Nigeria and Australia [ 18 , 19 , 37 ] and 15% of reported snakebite cases in Brazil [ 38 ]. The reasons are most likely due to children’s playing activities, inquisitive nature, and lack of appreciation for the health risk associated with a snakebite.…”

“…A study from Nigeria reported that children with cytotoxic SBE are more likely to need an amputation, blood transfusion, and antivenom than adults [ 19 , 40 ]. Antivenom is more commonly prescribed for children with snakebite than adults in sub-Saharan Africa, with the proportion ranging from 15–85% [ 13 , 15 , 18 , 19 , 20 ]. One study in India reported an odds ratio of 2.97 for a poor outcome (mortality, ventilation, or renal replacement therapy) in children under 5 years of age [ 13 ].…”

“…To add insult to injury, the rate of anaphylaxis from antivenom in children is higher than in adults. In East Africa, the rate of acute allergic reactions from several different antivenom products was reported at 17.6% in children [ 18 ]. The less-purified polyvalent antivenoms are more likely to cause allergic reactions and anaphylaxis than the more-purified or monovalent antivenom products.…”

“…Authors in north Africa reported elevated leucocytes and elevated CK levels as independent predictors of severity, while low platelets were associated with more severe presentations [ 24 ]. In sub–Saharan Africa, low haemoglobin, raised leucocytes, and low serum sodium were independently associated with severity in envenomed children [ 18 ]. Although some explanations for abnormal blood results are speculative, some mechanisms have been proposed.…”