This is the second of two posts on measles and North Carolina public health law. The first post addressed the laws that require children in the state to be immunized against measles as a preventative action. This post focuses on state laws that establish communicable disease control measures—that is, the steps that are taken to control the spread of a disease once it has been introduced into the state.
What is the relationship between vaccination against measles and measles control measures?
North Carolina children are required to be vaccinated against measles unless they are exempt, as I explained in my previous post. However, the state laws that establish the childhood immunization requirements (to prevent occurrence of disease) and the laws that require compliance with communicable disease control measures (to manage the spread of disease once it occurs) are different. Although vaccination is the primary method used to prevent measles in North Carolina[1] and is required under the state’s immunization laws, vaccination against measles is not required as a control measure under the laws described in this post, which come into play only after measles is present in a community.
What are North Carolina’s communicable disease control measures and who establishes them?
There are dozens of communicable diseases that are of concern to public health, and they vary in many ways that are relevant to determining how to control their spread. As a result, there are no one-size-fits-all communicable disease control measures. The specific actions or steps that are needed are disease-specific.
A state law directs the North Carolina Commission for Public Health (hereafter “Commission”) to adopt rules establishing communicable disease control measures.[2] The same statute requires all persons to comply with the control measures the Commission adopts. G.S. 130A-144. The Commission’s rules establishing communicable disease control measures are published in the North Carolina Administrative Code.
How do North Carolina public health officials determine which control measures are required for a particular communicable disease?
The Commission has adopted rules with specific control measures for only a few communicable diseases and conditions—namely, HIV, hepatitis B and C, sexually transmitted diseases, tuberculosis, smallpox/vaccinia, and SARS (severe acute respiratory syndrome). For other communicable diseases, including measles, the Commission’s rules provide that the communicable disease control measures will be derived from other sources or devised by public health officials.
Communicable disease control measures are normally derived from the Centers for Disease Control & Prevention’s (CDC) published guidelines and recommended actions for the particular disease. If CDC guidelines don’t exist or are insufficient, control measures are derived from the guidelines and recommendations that appear in the Control of Communicable Diseases Manual, a publication of the American Public Health Association (APHA). Both the CDC guidelines and the APHA manual are incorporated by reference into the Commission’s control measure rules. 10A N.C.A.C. 41A .0201(a).
The rules prescribe general principles that public health officials must follow in interpreting and implementing the control measures derived from those sources. Those principles require taking into account the way the particular disease is transmitted, and ensuring that the control measures that are implemented are reasonably expected to decrease the risk of transmission and consistent with recent scientific and public health information. For a disease that is transmitted by the airborne route, such as measles, the rules provide that physical isolation shall be required for “the duration of infectivity”—or in layperson terms, for as long as the person is capable of infecting others. 10A N.C.A.C. 41A .0201(b).
What are the control measures for measles?
The CDC’s published guidelines for measles focus on individuals who either have measles or are exposed to measles. The control measures include isolation of people who have measles, contact tracing to identify people who have been exposed to a person with measles, and quarantine of exposed persons if they do not have “presumptive evidence of immunity” to measles.
In general, “presumptive evidence of immunity” to measles is established by any one of the following:
- Documentation of adequate vaccination against measles,
- Laboratory evidence of immunity to measles (a blood test that shows certain antibodies),
- Documentation of having had confirmed measles in the past, or
- Birth before 1957.[3]
If an exposed person does not have presumptive evidence of immunity, post-exposure prophylaxis (PEP) may be offered if the person’s exposure was recent enough for the PEP to be effective. There are two types of PEP for measles. The first is the MMR vaccine, which can prevent measles if it is administered within 72 hours of exposure. The second is immunoglobulin, which must be administered within 6 days of exposure and is an option only for a small group of people at increased risk of severe outcomes from measles (infants under 12 months, pregnant women, and immunocompromised people).
The MMR vaccine is the only form of PEP that allows an exposed person to avoid quarantine. Otherwise, an exposed person who does not have presumptive evidence of immunity to measles must be quarantined.
Who can order isolation or quarantine for measles?
Isolation or quarantine may be ordered by either a local health director (the public health official who leads the local health department) or the State Health Director. GS 130A-145. In practice, isolation and quarantine orders are almost always issued locally, by the local health director.
What does isolation or quarantine require?
Isolation orders are used for individuals who have measles or are reasonably suspected of having measles. Quarantine orders are used for individuals without presumptive evidence of immunity who have been exposed to measles or are reasonably suspected of having been exposed.
Individuals who have measles must be isolated until four days after the onset of the measles rash. At that point, they are no longer considered to be infectious. A person under isolation for measles must remain at home and avoid contact with any persons other than household members. The person must not attend school, child care, or work. If medical care is needed, the person (or parent, if the person is a child) is instructed to call ahead to the health care facility and let them know that they have measles, so that the facility can instruct them in how to seek care without endangering other patients in the facility (for example, by waiting in the car or entering the facility through a separate entrance). In a medical emergency or other situation requiring a 911 call, first responders should be notified that the person has measles.
Individuals who are exposed to measles will be assessed for presumptive evidence of immunity and may be offered PEP. An exposed person who does not have presumptive evidence of immunity and does not receive the MMR vaccine as PEP must quarantine for 21 days after exposure. People under quarantine for measles are not generally required to stay at home at all times, but they must not attend work, school, or child care, and they must avoid enclosed settings where people congregate. The exposed person (or parent, if it’s a child) must notify the local health department if the person develops a cough, runny nose, watery red eyes, fever, or a rash. If medical care or emergency services are needed, the person (or parent) should call ahead to the health care facility or notify first responders that they are under quarantine for measles exposure.
Exposed individuals who have evidence of immunity or who receive the MMR vaccine as PEP within the 72-hour window are not required to quarantine. However, all exposed persons, regardless of evidence of immunity or vaccination status, are advised to self-monitor for symptoms of measles and seek medical care if symptoms develop. If medical care is needed, the person (or parent) should call ahead to the health care facility and let them know about the measles exposure.
Where can I find more information about measles and the current outbreaks?
The state and federal governments both maintain websites with further information and resources about measles. The websites include regularly updated data about the current outbreaks.
N.C. Division of Public Health:
CDC:
Conclusion
The CDC and the North Carolina Division of Public Health both recommend vaccination against measles to protect individuals from getting measles and to interrupt outbreaks. In North Carolina, requiring children to be vaccinated is the primary law-backed public health strategy for managing measles.
When measles cases or outbreaks occur, the communicable disease control measure laws come into play and require all persons to comply with control measures established by the Commission for Public Health. Those control measures require the isolation of individuals with measles, and quarantine for exposed individuals who do not have presumptive evidence of immunity to measles and do not receive the MMR vaccine within 72 hours of exposure.
[1] According to the Centers for Disease Control and Prevention (CDC), a two-dose regimen of the MMR (measles, mumps and rubella) vaccine is 97% effective against measles and confers lifetime immunity for most people. The recently revised federal vaccine recommendations continued the long-standing recommendation that all children be vaccinated against measles. The CDC also cautions that communities are more vulnerable to a measles outbreak when less than 95% of community members are vaccinated.
[2] North Carolina uses the term “communicable disease control measures” but does not define it. In practice, the term is understood to mean the actions or steps intended to prevent or reduce the spread of a communicable disease.
[3] Adults born before 1957 are presumed to have had measles as children. Individuals in this group who are uncertain about their personal measles history are still generally treated as presumptively immune for purposes of control measures, but are encouraged to discuss the situation with their health care providers if they are concerned or at risk of exposure.
