Tom Pelissero

USA TODAY Sports

The NFL's infectious disease consultants sent a letter to team doctors and athletic trainers this week outlining the risk of transmission of the Ebola virus and saying they are not recommending new procedures or widespread screening for possible contact with infected patients at this time.

In the letter, obtained by USA TODAY Sports, two doctors from the Duke Infection Control Outreach Network wrote that transmission of Ebola from infected patients "is inefficient relative to a number of other infectious diseases" and has only been spread by direct physical contact.

The risk of acquiring Ebola has "been skewed in many news articles," the letter said, and for those not involved with caring for sick patients, that risk remains lower than dying from a dog attack, lightning or a plane crash.

"At this point we do not advise screening of players or staff to make sure that they have not had close contact with anyone who traveled to or from areas where Ebola is now endemic," the letter from Dr. Daniel J. Sexton and Dr. Deverick J. Anderson said.

"We do recommend that medical personnel educate their players and staff about the need to inform club medical personnel in the unlikely event that they actually have such contact. This information can then be used along with consultation with local public health departments and local infectious disease experts to assess whether any further actions are needed. …

"Medical personnel are frequent sources of information for worried individuals who do not have knowledge about medicine, infectious diseases, or the risk of many illnesses. We advise NFL medical personnel to 'stick to the basics' and utilize the preceding general principles when questions about risk of EVD or questions about potential exposures to Ebola arise."

The letter recommended that team personnel who become aware of possible exposure "seek advice from either an infectious diseases specialist affiliated with their team, team physicians, or with their local health department."

The full text of the letter is below:

Ebola: Basic Facts to Answer Common Questions

Introduction

The general public and medical community have been bombarded with news stories about the emergence of Ebola virus disease (EVD) in West Africa (Guinea, Sierra Leone, and Liberia) and its subsequent importation into the United States. These news stories emphasize the high mortality of EVD, the fact that transmission is occurring in several African countries, and that health care workers have died as a result of caring for infected patients. Furthermore, reports of Ebola transmission from sick patients to a nurse in Spain and another in Dallas have heightened the alarm about the risk of transmission of this virus. These stories have in turn produced fear in the general public. Our goal in writing this newsletter is to provide basic facts and answers to common questions that may arise in players, their families, or your staff—particularly if imported cases of Ebola have occurred in your local community.

Basic facts

Risk of transmission - Although mortality rates of patients with EVD are high, with the important exception of medical personnel who are directly caring for patients who are critically sick, transmission from infected patients is inefficient relative to a number of other infectious diseases. For example, only 1 in 6 direct household contacts of African patients with known EVD developed infection in a study done in the Congo during a prior outbreak (1). Furthermore, ALL of the household contacts who developed Ebola in this and subsequent outbreaks had direct physical contact with infected individuals. Thus, the scientific support for the following key educational message about Ebola risk remains true: Being in the proximity of a person with EVD does not result in a risk of transmission if there is no direct person-to-person contact.

Healthcare worker acquisition - A number of healthcare workers have acquired EVD while working in African hospitals that lacked basic isolation equipment and standard medical supplies, transmission remains uncommon but not impossible in modern healthcare settings. Two recent reports, one from Spain and another from Dallas, have documented that healthcare workers caring for critically ill patients with EVD can become infected during the process of performing intensive care. This risk, however, is dissimilar to the risk of casual contact with a patient who is ill with Ebola, particularly if contact is not direct or prolonged.

Environmental contamination - Despite recent news accounts of special HAZMAT teams decontaminating rooms of a person with EVD, the evidence that Ebola virus can be transmitted by indirect contact with environmental surfaces is weak thus far. For example, Ebola virus could not be recovered from any of 33 environmental samples taken from the hospital room of a patient with EVD in one report (2). And recent studies done in patients with EVD who were hospitalized at Emory University in the United States have shown similar findings. However, direct contact with vomit, sputum, diarrheal stool samples, or blood or bloody fluids is a risk factor for transmission. 2

No transmission without symptoms - The scientific evidence is compelling and convincing that exposed persons who have not yet developed fever or other signs of EVD are not infectious to others. In other words, non-symptomatic patients who are in the incubation period after exposure to Ebola virus are NOT infectious to others.

Key risk factor = travel – When questions about potential risk of acquiring EVD arise, the key question is "have you or anyone you've been in close contact with been to West Africa?" If the answer to this question is "no," the risk of acquiring EVD is extremely low. The CDC recently published a useful algorithm for evaluating patients who recently returned from high-risk areas in West Africa (Figure 1).

Perception is not reality - Perceptions of risk of acquiring EVD have been skewed in many news articles about the importation of EVD into the United States. Even if additional imported cases of EVD occur in the future, this risk among persons who are not involved with the direct care of sick patients will almost certainly remain far lower than the risk of other rare causes of death such as dying from a dog bite or attack (1 in 104,000), lightning strikes (1 in 136,000), or a plane crash (1 in 1,100,000).

Useful advice

At this point we do not advise screening of players or staff to make sure that they have not had close contact with anyone who traveled to or from areas where Ebola is now endemic. We do recommend that medical personnel educate their players and staff about the need to inform club medical personnel in the unlikely event that they actually have such contact. This information can then be used along with consultation with local public health departments and local infectious disease experts to assess whether any further actions are needed.

Other than the recommendation that medical personnel educate their staff about the need to report exposures to persons who recently traveled to or from West Africa, additional new policies, procedures or activities by team physicians and athletic trainers designed to prevent Ebola infections in their team members are not recommended.

Medical personnel are frequent sources of information for worried individuals who do not have knowledge about medicine, infectious diseases, or the risk of many illnesses. We advise NFL medical personnel to "stick to the basics" and utilize the preceding general principles when questions about risk of EVD or questions about potential exposures to Ebola arise.

The following websites and agencies provide up to date information about the epidemiology and transmission of Ebola virus and the clinical features of EVD, which, fortunately, remains uncommon despite its high profile in the news.

http://www.cdc.gov/vhf/ebola/index.html

http://globalhealth.duke.edu/ebola

http://www.who.int/csr/disease/ebola/en/

Finally, if any NFL personnel encounter situations or questions about possible exposure to Ebola virus in team personnel or their family members, we recommend that they seek advice from either an infectious diseases specialist affiliated with their team, team physicians, or with their local health department. Team medical personnel can also request further information or advice, if necessary, from their state health department and/or the Centers for Diseases Control should special circumstances warrant such action.

Daniel J. Sexton, MD

Deverick J. Anderson, MD, MPH