According to a systematic review and meta-analysis, children who are rural-urban migrants in China, India and Nigeria were less likely to be fully-immunized by the age of one year than non-migrant urban residents and the general population. These inequities in vaccination rates — often concealed in national averages — call for special efforts to improve immunization rates in this rapidly growing sub-population to reduce both health inequities and the risk of infectious disease outbreaks in the wider society.
South-East Asia
Administering hepatitis B immune globulin to newborns in addition to vaccination prevents more infections and is cost-effective
In a study of different strategies for preventing hepatitis B infections in newborns in a Burmese refugee population with a high infection rate, administering hepatitis B immune globulin to newborns whose mothers test positive through a rapid diagnostic test — in addition to vaccinating all newborns with a birth dose — prevented twice as many infections in newborns than vaccination alone and was cost-effective (while the current strategy of providing immune globulin only after a confirmatory lab test was done was not). Thus, this strategy could be considered for similar marginalized or poor populations.
Vaccinating children in high-risk slum areas in Bangladesh can effectively control cholera and save lives
A study using local epidemiological and economic data found that vaccinating children 1-14 years old in high-risk slum areas in Dhaka, Bangladesh using a locally-produced oral cholera vaccine provided through periodic campaigns would be a highly cost-effective means of controlling endemic cholera — reducing cholera incidence in the entire population by 45% over 10 years and costing US$440-635 per DALY averted. Vaccinating all persons aged one and above would reduce incidence much further (by 91%) but would be less cost-effective.
Dengue illness is costly for low-income families, but immunization can help reduce the economic burden
In a standardized survey of the costs of dengue illness in three highly endemic countries, the economic burden of dengue was greatest on Vietnamese and Colombian low-income families, whose total costs, including lost wages, outpatient and inpatient cases combined, average 36-45% of their monthly household income. In Thailand, although significant, the economic burden was 17% less than the other countries, due to Thailand’s universal health insurance system.
HIV-exposed infants are more vulnerable to measles due to lower levels of antibodies
A small hospital-based study in India found that 6 month old infants born to HIV-infected women were 11 times more likely to lack measles antibodies than 6 month olds not exposed to HIV whether or not the exposed infants were themselves infected with HIV. The lack of antibodies in most HIV-exposed infants — making them more vulnerable to measles — may be due to lower levels of measles antibodies in HIV-infected mothers or to poorer transfer of antibodies to the fetus across the placenta.
The introduction of the Hib vaccine in Tamil Nadu led to a 79% decline in meningitis cases in children under two years
In a major children’s hospital in the Indian state of Tamil Nadu, meningitis cases caused by Haemophilus influenzae type b (Hib) in children under two years declined by 79% within two years of the introduction of Hib vaccine. This decline was greater than expected given a vaccination coverage of ~70% for one dose of the vaccine and much greater than expected with a 53% coverage rate for three doses. This suggests that the vaccine protected unvaccinated children through herd immunity.
Children of migrant laborers may have lower vaccination rates compared to the general population, increasing their risk of preventable diseases
A study found that children of poor labor migrants living in Delhi, India are much less likely to be fully vaccinated than the general population and thus are at greater risk of vaccine-preventable diseases. Only 31% – 53% of children from migrant families were fully immunized (against 7 diseases) by 12 months of age, compared to 72% in the overall population of Delhi — with recent migrants having the lowest rates. There is therefore a need to focus on the delivery of health services to migrants.
Efforts to eradicate polio have also led to improved access to other vaccines
The expertise and assets gained through efforts to eradicate polio at least partially explain the improvement between 2013 and 2015 in vaccination coverage of DPT3 in six out of ten “focus” countries of the Polio Eradication Endgame strategic plan. This includes substantial increases in vaccination rates in India, Nigeria, and Ethiopia, which, combined, reduced the number of children not fully vaccinated with DPT by 2 million in 2 years.
Immunizing children against rotavirus saves money and prevents hospitalizations and outpatient visits
Vaccinating children against rotavirus in Bangladesh would prevent more than 50,000 outpatient visits and 40,000 hospitalizations in children under five each year, and reduce treatment costs by US$5.8 million over 2 years — nearly all (96%) from fewer hospitalizations. Since this study didn’t take herd effects into account, the actual impact would likely be greater.
Immunizing infants and older age groups against typhoid can save costs and be economically justifiable
The first study of the cost-effectiveness of typhoid conjugate vaccines found that routinely immunizing infants at 9 months of age would actually save costs in 2 settings (Delhi, India and a rural area of Vietnam), due to high incidence or high hospitalization rates, and would be cost-effective in the study’s 3 other sites (in India and Kenya). Adding a one-time catch-up campaign for various older age groups would still save costs in Delhi and Vietnam, and increase the cost-effectiveness in the others, making it economically justifiable.