Infectious Disease Surveillance
The next morning you arrive in Sparta and meet with Bernard Barstow, the Director of the Sparta Health Department. He thanks you for coming out and gives a little more background regarding the outbreak. Play the video below to hear what he has to say (1:05).
Barstow continues:
"We generally see less than 5 cases of hepatitis A each year in Sparta scattered throughout the year. Whenever a case occurs, we investigate to try to ascertain the source and to prevent any additional spread. If it involves a diapered child, or a day-care attendee, or a food handler, we want to prevent further transmission. These sporadic cases tend to be the result of travel outside the US, or from household or sexual contact with an infected person; about half the time we never figure out what the source was. In this case, we were first alerted when the emergency room physician reported the occurrence of hepatitis A in the 31 year-old woman. Over the next several days three other local physicians called the board of health and reported four more cases, so we began to think that this was more than the usual sporadic cases.
"Massachusetts now uses on online reporting system for surveillance of reportable infectious diseases. It's called MAVEN, which stands for Massachusetts Virtual Epidemiologic Network. This system provides a uniform means by which hospitals, laboratories, and health departments across the state can report relevant information about anyone who has developed a reportable infectious disease. This has greatly speeded up reporting and case investigation, and it makes it possible to look for trends and epidemics across the state. Other states are beginning to use similar systems for infectious disease surveillance. However, in addition to reporting cases to the MAVEN system, we also keep our own listing of all reportable cases in our town. This comes in handy if we have reason to suspect that there may be an infectious disease outbreak
."
Disease surveillance is a primary function of public health. A good way to quickly learn how disease surveillance functions is to take a look at this online module on Disease Surveillance.
Reportable Diseases
"State laws require that certain diseases be reported in order to identify health problems that require attention and to monitor changes in disease frequency over time. In Massachusetts the state DPH has the authority to determine which diseases must be reported and how. State law specifically lists these diseases and stipulates that household members, physicians and other health care providers must promptly report cases to the local board of health; the local board is then required to report this information (including the case's name, date of birth, age, sex, address and disease) to the state Department of Public Health (DPH). Similarly, all laboratories, including those outside of Massachusetts, performing examinations on any specimens derived from Massachusetts residents that yield evidence of reportable infections must be reported to the Massachusetts DPH. These state laws and regulations provide the basis for an ongoing system of disease surveillance."
"Surveillance data is important for identifying sudden increases in disease occurrence, but it's also important for following secular (long-term) trends and patterns of disease. For example, it would be useful to keep tabs on the frequency of cases of West Nile virus to guide decisions about mosquito control. In addition, surveillance data for HIV would be important for following long-term trends and to anticipate the needs of the population. Surveillance data is also useful for monitoring the effectiveness of prevention programs. And finally, surveillance data sometimes generate hypotheses. For example, in 1980 it was discovered that many of the cases of toxic shock syndrome occurred in menstruating women. This led to research that demonstrated that the syndrome was associated with a particular brand of tampon, and the product was promptly removed from the market."
Take a look at this online module which has more detailed information about Infectious Disease Surveillance in Massachusetts.
Additional Resources:
Privacy of Medical Information
One of Barstow's coworkers turns to you and says, "I don't get it. What about the regulations in the Health Insurance Portability and Accountability Act (HIPAA)? With all these HIPAA regulations on privacy of medical information, how can doctors, hospitals and labs report diseases to the local or state departments of health with personal identifiers?"
Other resources regarding confidentiality of health-related information:
- Code of Massachusetts Regulations (CMR) Reportable Diseases and Confidentiality
- MDPH Memo to Local Boards of Health
- MDPH Memo to Hospitals, Clinics, Health Care Facilities, and Clinical Laboratories
Barstow summarizes the information in these documents and continues:
"When we saw the first group of cases, I sent a notice to the local hospitals, clinics, clinical laboratories, and local area physicians, indicating that a cluster of four cases of hepatitis A had been identified, and I reminded them that if they saw any evidence of new cases of hepatitis A, they were required to report them to the Department of Public Health promptly.
