Pennsylvania has asked the United States Centers for Disease Control and Prevention (CDC) for help containing an expanding measles outbreak that has seen several people die, but says it will withdraw the request unless the federal agency recognises four measles-associated deaths reported by the state.
The CDC, however, said it has not been properly notified of any such request.
The US is currently seeing the worst measles outbreak in the country since 1991, with several deaths over the last couple of years. Measles was declared eliminated in the US in 2000, but has made a comeback in recent years, which some have linked to a rise in vaccine scepticism. The US state of Pennsylvania has been hit especially hard.
In a letter sent to CDC Director Erica Schwartz on Wednesday, Pennsylvania Health Secretary Debra Bogen said the state had begun the process of requesting emergency assistance from the CDC, known as an Epi-Aid.
“The CDC’s choice not to publicly recognize the deaths undermines our response,” Bogen wrote. “For this reason, if CDC is unable to transparently and accurately communicate information about those measles-associated deaths, the Department will respectfully rescind our request for a CDC Epi-Aid.”
However, in a statement to Al Jazeera, Grace Davis Jamison, press secretary for the US Department of Health and Human Services (HHS), said that the CDC had not received Pennsylvania’s request through its normal channels and that federal outbreak assistance was separate from how the agency tabulates deaths.
“CDC will not allow [Pennsylvania Democratic] Governor [Josh] Shapiro to politicize this process. We owe the American people accurate, consistent, and transparent public health information,” Jamison said. “CDC will not submit to political blackmail that conditions critical public health assistance. The people of Pennsylvania should never be used as leverage in a political dispute over how deaths are classified.”
The dispute over the deaths began in August, when Pennsylvania reported that two unvaccinated people died of measles in Lancaster County, which is located in the South Central part of the state. Lancaster is considered the centre of Pennsylvania Dutch Country and home to the nation’s oldest Amish and Mennonite communities. Both communities have under-vaccinated populations.
The CDC initially included the deaths in its national tally, but subsequently removed them after Health Secretary Robert F Kennedy Jr questioned whether measles had caused or contributed to the fatalities. The agency said at the time that available information did not establish whether measles caused or contributed to the deaths.
Pennsylvania continued to stand by its determination.
The outbreak has spread well beyond its initial epicentre in Lancaster County. On September 13, a county coroner reported that a 40-year-old woman had died from complications associated with measles. The state later confirmed the death as measles-associated and announced two additional deaths on September 15. All four people were unvaccinated, according to the state.
The state reported 393 cases across 28 counties when the first two deaths were announced on August 25. Pennsylvania now reports 731 confirmed cases across 38 counties and 141 hospitalisations. Of those reported cases, only four people, or less than one percent, are vaccinated.
The disagreement between Pennsylvania and the CDC centres on the distinction between a “measles-associated” death versus a death “caused” by measles. Pennsylvania uses “measles-associated” under its state surveillance definition, while HHS said it is working with the Council of State and Territorial Epidemiologists to establish a standardised definition for measles deaths.
Infectious disease experts warn that the dispute over how to classify the deaths puts the CDC at odds with a long-standing approach to tracking the consequences of measles. Matthew Ferrari, director of Pennsylvania State University’s Center for Infectious Disease Dynamics, told Al Jazeera that “measles-associated” death has long been a standard used by the World Health Organization and CDC.
“It’s the most useful distinction because it is a case that could have been prevented by a measles vaccination, or by early detection and isolation,” Ferrari said. “Measles is severely immunocompromising, so it is very often a secondary infection that is the ultimate cause of death.”
Experts say the CDC’s dispute with Pennsylvania risks distracting from efforts to contain the outbreak. Dr Andrew Pavia, spokesperson for the Infectious Diseases Society of America and professor at the University of Utah, told Al Jazeera the distinction should not be controversial.
“The impact, though, is confusion for the public and erosion of trust in the ability of CDC staff to communicate to the public without political interference,” Pavia said.
HHS said federal outbreak assistance and national mortality reporting are separate processes and rejected the idea that the two should be linked.
An Epi-Aid is a CDC mechanism for providing rapid, short-term assistance during an urgent public health problem. The CDC says Epi-Aids generally last one to three weeks, during which they deploy Epidemic Intelligence Service officers to analyse epidemiological data, evaluate surveillance systems, and recommend measures to control and prevent the spread of disease.
The requesting health authority retains overall leadership of the investigation, while CDC personnel provide technical assistance, including epidemiological expertise and access to laboratory resources.
“The most important thing for an effective response is communication and trust,” Ferrari said. “It is important for all partners to agree on the foundational elements of the problem and the metrics for evaluating the severity of the problem.”