In rural Tanzania, babies born small are actually less likely to miss their vaccines than babies born at a normal weight — the opposite of what’s seen in most other poor countries.

Scientific Claim

In rural Tanzania, infants with low birth weight have a 29% lower risk of delayed or incomplete DTP3 vaccination compared to normal birth weight infants, a counterintuitive finding that contrasts with patterns observed in other low- and middle-income countries.

Original Statement

“In Morogoro region, low birthweight infants had 31% (95% CI: 20–40%) and 29% (95% CI: 21–36%) reduced risk of delayed or not received DTP1 and DTP3 vaccination, respectively.”

From study:Determinants of delayed or incomplete diphtheria-tetanus-pertussis vaccination in parallel urban and rural birth cohorts of 30,956 infants in Tanzania

Evidence Quality Assessment

Claim Status

appropriately stated

Study Design Support

Design supports claim

Appropriate Language Strength

association

Can only show association/correlation

Assessment Explanation

The study reports reduced risk with confidence intervals and explicitly notes this contradicts other studies. No causal language is used, making the statement appropriate for an observational design.

Evidence from Studies

Supporting (0)

No supporting evidence found

Contradicting (1)

Determinants of delayed or incomplete diphtheria-tetanus-pertussis vaccination in parallel urban and rural birth cohorts of 30,956 infants in Tanzania

Cohort Study

Human

2019 Feb 26

The study looked at why babies in rural Tanzania didn’t get their vaccines on time, but it never mentioned how much the babies weighed at birth — so it can’t say whether low-weight babies are more or less likely to be vaccinated.

Source Study

Determinants of delayed or incomplete diphtheria-tetanus-pertussis vaccination in parallel urban and rural birth cohorts of 30,956 infants in Tanzania

Score: 66

DOI: 10.1186/s12879-019-3828-3

Similar Assertions

In rural Tanzania, babies born at home are more likely to be late or miss their vaccines than babies born in hospitals or clinics.

90%

In both cities and rural areas of Tanzania, babies from the poorest families are more likely to be late or miss their vaccines than babies from the richest families.

88%

In rural Tanzania, babies who are the fifth or later child in their family are more likely to be late on their vaccines than the first child.

88%

In both cities and rural areas of Tanzania, teenage moms are much more likely to have babies who miss or are late on their vaccines than moms in their mid-20s.

87%

In both cities and rural areas of Tanzania, about 1 in 6 babies are late or miss their third vaccine shot — even though the reasons are different.

86%