An old disease, pertussis or whooping cough, reemerged this summer in California and crept into the Pacific Northwest. At least one infectious disease expert explained the epidemic by calling the region the “epicenter of vaccine refusal.” Meanwhile, another pattern has emerged: 9 of the 10 infants who have died from infection were Latino.
As of Oct. 26, there were 6,257 cases reported in California — the most since 1950, when 6,613 cases were reported. Ten people have died, all infants. (More on Time.com: The Hispanic Mortality Paradox: Why Do Latinos Outlive Other Americans?).
In absolute numbers, whites account for most of the caseload, but proportionally the Latino community has been harder hit with rates of 16.5 cases per 100,000 people versus 13.6 cases per 100,000 white people.
Once age enters the equation, Latinos’ overrepresentation is even more marked: the rate of pertussis in Hispanic infants younger than 6 months was 395.9 cases per 100,000 babies, and these children accounted for 76% of all hospitalized infants, according to the California Department of Public Health. (More on Time.com: Top 10 Terrible Epidemics).
Health officials suggest that Hispanic babies are particularly vulnerable in part because of their living situation; they are more likely to live with a greater number of people, upping their chances of exposure to upper respiratory illness. And the famously close-knit family units that keep Latinos living longer may in this instance expose babies to unvaccinated aunts, uncles and grandparents.
Since infants cannot receive the whooping cough vaccination until they are at least 2 months old, the only defense that newborns have is avoiding those who have not been immunized: 90% of unvaccinated children who live with someone who gets pertussis will also get the disease, according to immunization research.
More on Time.com: