Does vitamin A supplementation have a therapeutic effect on measles in the United States of America (USA)?

From the Guidelines

Vitamin A supplementation is recommended for certain cases of measles in the United States, specifically for children with complicated measles, as it has been shown to reduce mortality and complications in these patients. The Centers for Disease Control and Prevention (CDC) recommends vitamin A for children with complicated measles, such as those with pneumonia, otitis, croup, diarrhea with moderate or severe dehydration, or neurological problems, as stated in the 1992 guidelines 1. The recommended dosage is not explicitly stated in the provided evidence, but according to general guidelines, it is typically 200,000 IU for children 12 months or older, 100,000 IU for 6-11 month olds, and 50,000 IU for infants under 6 months, given once daily for two days.

Key Points to Consider

• Vitamin A supplementation is not routinely recommended for all measles cases in the United States, but rather for specific cases with complications or certain risk factors.
• The CDC recommends vitamin A for children aged 6 months to 2 years hospitalized with measles, children over 6 months with impaired immunity, those with clinical signs of vitamin A deficiency, and those with severe complications of measles.
• Measles remains a significant public health concern, with ongoing international importations and potential for transmission among unvaccinated populations in the United States, as highlighted in the 2011 report 1.
• High vaccine coverage in the United States has been crucial in controlling measles, with 91.5% of children aged 19–35 months having received 1 dose of MMR vaccine in 2010, and 94.8% of kindergartners having evidence of 2 doses in 2009-2010 1.

Clinical Implications

• Healthcare providers should be aware of the CDC's recommendations for vitamin A supplementation in measles cases and apply them accordingly.
• Standard care for measles in the U.S. primarily focuses on supportive treatment, including ensuring adequate hydration, fever management, and preventing secondary infections.
• Vitamin A works by helping maintain epithelial tissue integrity and immune function, which are compromised during measles infection, as supported by the 1992 guidelines 1.

From the Research

Vitamin A Supplementation and Measles in the USA

• The therapeutic effect of vitamin A supplementation on measles in the United States of America (USA) is not directly addressed in the provided studies, as they focus on global or high-income country settings rather than specifically on the USA 2, 3, 4, 5, 6.
• However, the studies suggest that vitamin A supplementation can have a beneficial effect on measles outcomes in certain contexts, such as in areas where vitamin A deficiency is present or in children under the age of two years 2, 3.
• A study conducted in a high-income country (Italy) found that vitamin A supplementation did not reduce the risk of complications or change the clinical course of measles infection in children hospitalized for measles 4.
• Other studies have reported that vitamin A supplementation can reduce mortality and complications resulting from measles, particularly in populations with vitamin A deficiency 5, 6.
• The effectiveness of vitamin A supplementation in reducing morbidity and mortality in children may depend on various factors, including the population's nutritional status and the presence of vitamin A deficiency 6.

Key Findings

• Two doses of vitamin A (200,000 IU) given on consecutive days were associated with a reduced risk of mortality in children under the age of two years and a reduction in pneumonia-specific mortality 2, 3.
• Vitamin A supplementation was not found to be effective in reducing the risk of complications or changing the clinical course of measles infection in children hospitalized in a high-income country 4.
• Vitamin A deficiency is a recognized risk factor for severe measles infections, and supplementation may be beneficial in populations with vitamin A deficiency 5, 6.

Study Limitations

• The studies had varying sample sizes, populations, and settings, which may limit the generalizability of the findings to the USA or other specific contexts 2, 3, 4, 5, 6.
• Some studies had methodological limitations, such as the lack of direct comparison between single and double doses of vitamin A 2, 3.