December 2019

Emerging Infectious Diseases Journal

Highlights: Emerging Infectious Diseases, Vol. 25, No. 12, December 2019

Important Note: Not all articles that EID publishes represent work done at CDC or by CDC staff. In your stories, please clarify whether a study was conducted by CDC (“a CDC study”) or by another institution (“a study published by CDC in the EID journal”). Opinions expressed by authors contributing to EID do not necessarily reflect the opinions of CDC or the institutions with which the authors are affiliated. EID requests that, when possible, you include a live link to the actual journal article in your stories. Once the embargo lifts, this month’s articles will be found in the Ahead of Print section of the EID website at

The articles of interest summarized below will appear in the December 2019 issue of Emerging Infectious Diseases, CDC’s monthly peer-reviewed public health journal. This issue will feature Emerging Viruses. The articles are embargoed until November 14, 2019, at 12 p.m. EDT.

1.     Seroprevalence and Risk Factors Possibly Associated with Emerging Zoonotic Vaccinia Virus in a Farming Community, Colombia, Ashley Styczynski et al.

Vaccinia virus (VACV) is a member of the genus Orthopoxvirus within the family Poxviridae, along with other notable poxviruses such as cowpox, monkeypox, and variola (the causative agent of smallpox). VACV has been invaluable in its use as the vaccine against smallpox in humans. However, VACV can also infect nonhuman hosts, such as cattle, and researchers have long speculated that the virus might have spread to animals during the worldwide smallpox eradication effort decades ago. In the wake of a 2014 outbreak of laboratory-confirmed VACV infections among dairy farmworkers and their household members in the municipality of Medina in Cundinamarca Department, Colombia, researchers conducted blood tests and risk factor assessments among the affected population. Fifty-two percent of farmworkers or their household members had orthopoxvirus antibodies (a sign that they had been exposed to an orthopoxvirus). This percentage decreased to 31% after researchers excluded persons who would have been eligible for smallpox vaccination during the eradication campaign. The major risk factors for seropositivity (i.e., having antibodies detected in blood) were residing in the affected municipality, age, presence of a smallpox vaccination scar, duration of time working on a farm, and animals on the farm having vaccinia-like lesions. Vaccinia-like lesions among farmworkers resulted in loss of productive work days and increased utilization of healthcare services, and vaccinia-like lesions among cattle resulted in decreased milk production, thus carrying significant economic ramifications. The investigation demonstrated that VACV might be an increasingly important zoonotic disease in this part of the world. Additional research will be important for directing public health efforts to raise awareness and implement preventive measures to minimize the animal, human, and economic toll of VACV infection.

Contact: CDC Media Relations; phone: 404-639-3286 or email:

2.    Animal Exposure and Human Plague, United States, 1970–2017, Stefanie B. Campbell et al.

Plague is a rare, life-threatening disease caused by Yersinia pestis bacteria. The bacteria survives in nature in rodents and their fleas. Different types of exposure (flea bites, contact with tissues of infected animals, or inhalation of infectious droplets from animals or humans) result in different forms of human illness (e.g., bubonic, pneumonic). Animals may be linked to human plague directly, such as caring for a plague-infected animal, or indirectly, such as fostering human contact with infected fleas. To learn more about the role of animals in human exposure to Y. pestis, researchers reviewed data from all 482 human plague cases reported in the United States during 1970–2017 and found that more than half of patients with plague had interacted with domestic or wild animals in ways that might have led to infection. Among those with pneumonic plague, the most severe and rapidly fatal form, nearly all had interacted with animals prior to illness. The frequency of animal contact among U.S. patients with plague highlights potential opportunities to enhance and refine prevention messages.

Contact: CDC Media Relations; phone: 404-639-3286 or email:

3.      Cost-Effectiveness of Prophylactic Zika Virus Vaccine in the Americas, A. Shoukat et al.

Zika virus remains a major public health concern because of its association with microcephaly and other neurologic disorders in children born to infected mothers. A vaccine to prevent Zika virus infection (prophylactic vaccine) could reduce disease and birth defects.  This study examines the cost-effectiveness of a Zika vaccine. Researchers created a statistical model to evaluate cost-effectiveness of a candidate Zika vaccine (vaccine still undergoing testing). The model assumed 60%–90% protection for women in 18 countries affected by the 2015–2017 outbreaks in the Americas and considered the susceptibility of the human population, the mosquito population, the cost of treatment for a patient with the disease, and the cost of vaccinating to prevent the disease. The model indicated that at $16 or less per vaccination, vaccinating women of reproductive age during an outbreak would be cost-effective and would prevent about three quarters of microcephaly cases.

Contact: Seyed M. Moghadas, York University, email:



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