Vitamin A supplementation reduces Measles Mortality and Severity

Uptake of certain micro-nutrients can make viral infections, especially respiratory viral infections, more or less severe. Just as vitamin D supplementation has been found to reduce adverse outcomes from SARS coronavirus infections (see Vitamin D as a COVID-19 Prophylaxis) for patients with insufficient/deficient vitamin D serum contractions, which is almost half the U.S. population (see previous answer), and COVID-19 itself depletes vitamin D serum, vitamin A supplementation has been found to reduce adverse outcomes from measles and the disease itself has been found to deplete vitamin A serum concentrations.

According to an editorial published in the British Medical Journal the observation that vitamin A supplementation could reduce measles mortality was first made by a British doctor in 1932 who found that the children who received vitamin A and D supplements had half the measles mortality rate of children who received the standard of care at that time. The hypothesis wasn’t retested until 1987 when another British doctor found, through a RCT, that vitamin A supplementation reduced measles mortality among pediatric patients in Tanzania by half. They note that serum vitamin A concentrations of well nourished children with measles are found to drop to levels lower than serum concentrations found in malnourished children without measles which suggests that measles itself depletes serum vitamin A.

A double blind placebo controlled RCT conducted among pediatric measles patients in South Africa (n = 189) found that 120 mg doses of vitamin A significantly reduced measles mortality and morbidity. Vitamin A supplementation at the aforementioned dose was found to cut the duration of pneumonia in half, the duration of diarrhea by a third and hospitalization by a third of the time of the standard of care group. Vitamin A supplementation reduced the relative risk of mortality by 79%, postmeasles croup by 49%, herpes stomatitis by 77%, and ICU admission by 62%. Overall, adverse outcomes were half as frequent in the vitamin A treatment group than the placebo group that received the standard of care.

A systematic review of RCTs and quasi-experimental studies examining the effectiveness of measles immunization (n = 35) and vitamin A treatment of measles pediatric patients (n = 7) found that ‘at least two vitamin A doses of 200,000 International Units for children more than a year old and 100,000 International Units for infants reduced measles mortality by 62%. The authors note that the substantial reduction in worldwide measles mortality between 2000 and 2007 was largely due to WHO/UNICEF programmes that provided vitamin A supplementation and measles immunization to children in developing countries and that vitamin A deficiency has been recognized as a risk factor for severe measles since 1987 (when the second study of Vitamin A efficacy for treating measles was done).

An earlier systematic review of RCTs examining the effectiveness of vitamin A treatment with pediatric measles patients in African countries (n = 5) found that two vitamin A doses 200,000 international units given on two different days reduced measles mortality by 64% and pneumonia specific mortality by 67% among hospitalized children in areas with high measles mortality with the greatest reduction in mortality being observed among measles patients under two years of age.