EXTRACTS FROM Texas Board of Medical Examiners:

Medical Board Report
Volume 21, Number 2
Spring 2000

Clarification on Lyme Disease

Following publication of the article on tick-borne diseases in the Fall 1999 Medical Board Report, the Board received requests for additional diagnostic information on Lyme disease, which occurs in Texas and is believed to be underreported by a factor of 10. The Lyme Disease Foundation and the Centers for Disease Control and Prevention say that the diagnosis must be clinical, based on signs and symptoms. No test can "rule out" Lyme disease. The following diagnostic tests may be used:

Antibody tests, which strive to be both sensitive (detecting LD antibodies) and specific (detecting just LD antibodies). False negatives and false positives can occur. Titer (ELISA or IFA) tests measure the level of Bb antibodies in fluid. Laboratories use different detection criteria, cutoff points, types of measurements and reagents.

Western blot produces bands indicating the immune system's reactivity to Bb. Laboratories differ in their interpretation and reporting of these bands.

Direct Detection Tests

Antigen detection tests detect unique Bb protein in fluid (e.g. urine) of patients. This may be useful for detecting LD in patients taking antibiotics or on symptom flare-up.

Polymerase chain reaction (PCR) test multiplies the chain reaction of Bb DNA to a detectable level to measure.

Culturing of the bacteria is difficult and can take months.

Staining of tissue is time-consuming and has a low yield.

Treatment

Treatment varies depending on how early a diagnosis is made. No definitive treatment regimens have been determined and failures occur with all protocols. Oral antibiotics may be sufficient for early stages of non-disseminated infection. Long-standing, disseminated disease responds best to one or several courses of intravenous antibiotics.

For additional information, consult the Lyme Disease Foundation at (860) 525-2000 or toll-free at (800) 886-LYME, or see the web site at www.lyme.org. Information on Lyme disease is also available from the CDC's web site at www.cd.cov/ncidod/publications/brochures/lyme.htm.

[See page 10] (below) for an important reminder about Health Department reporting requirements on this and other infectious diseases.


Disease Reporting Reminder

The Texas Department of Health reminds Texas physicians of their responsibility to report certain diseases in Texas. Failure to report is a Class B misdemeanor. Certain diseases, such as botulism, plague, rabies, meningococcal infections, diphtheria, measles (rubeola), and others, must be reported immediately by telephone. Rubella and tuberculosis must be reported within one day, and many other illnesses must be reported within one week. These include AIDS, brucellosis, dengue fever, hepatitis and many others. Reporting requirements include the disease, along with patient identifiers. For a complete list and additional information about reporting requirements, see the Fall 1998 issue of the Medical Board Report (listed below) or call TDH at 1-800-252-8239. To report diseases, call 1-800-705-8868.

Disease Reporting and Surveillance in Texas

Disease surveillance may be defined as the organized assembly, review, explanation, and distribution of data describing the occurrence of disease in a population. The ultimate purpose of maintaining such a system is reduction of disease frequency. In the historic past, disease surveillance was limited to analysis of mortality records. This method is still an important part of the analysis of human disease, but mortality records necessarily provide only superficial information from fatal events. By the mid-nineteenth century, disease surveillance in Europe and the United States placed special importance on the identification and quarantine of ill individuals. The more modern concept of surveillance is much broader, placing emphasis on the ecological explanation of disease in populations rather than on identifying affected individuals.

There are three basic forms of disease surveillance systems: active, passive, and sentinel. Active surveillance involves the routine collection of diagnostic information directly from health care facilities (hospitals, birthing centers, laboratories, and so on). Active surveillance yields the most reliable data on the actual prevalence of disease in a community, but it is prohibitively expensive in most settings. A passive surveillance system relies upon the initiative of health care professionals to report cases of notifiable diseases when they are diagnosed. It is, in effect, a voluntary system and is influenced by many factors including individual motivation. Passive surveillance is relatively inexpensive to conduct, but yields undercounts, often drastic undercounts, of disease occurrence. Sentinel surveillance narrows attention to a limited number of diseases, the identification of any one of which portends an ominous public health problem or indicates failure of the preventive care system. Sentinel surveillance is the least costly of the three systems to manage, but yields little in explaining patterns of disease frequency.

Texas relies upon a passive system for surveillance of infectious disease. Physicians, other health care providers, hospitals, laboratories, blood banks, school officials, and others who diagnose or are aware of cases of notifiable disease are required by law to report those cases appropriately. Specific regulations covering the reporting process are included in the Communicable Disease Prevention and Control Act (Section 81 of the Health and Safety Code), and Article 97, Title 25 of the Texas Administrative Code.

Each year, the Council of State and Territorial Epidemiologists, along with representatives from the Centers for Disease Control, convenes a meeting to review the list of reportable diseases and recommend additions or deletions in light of current knowledge, and to determine whether existing surveillance methods are sufficient to recover necessary information.

The current list of reportable diseases in Texas is given below. When identified, these diseases, along with patient identifiers, should be reported to the local health department or the Texas Department of Health at 1-800-252-9152.

Reportable immediately by telephone

Reportable within one day

rubella

tuberculosis

Reportable within one week

Acquired immune deficiency syndrome (AIDS)

Amebiasis

Anthrax

Asbestosis

Botulism (infant)

Brucellosis

Campylobacteriosis

Chancroid

Chlamydia trachomatis infection

Creutzfeldt-Jakob disease (CJD)

Cryptosporidiosis

Dengue fever

Ehrlichiosis

Encephalitis (specify etiology)

Escherichia coli 0157:H7 infection

Gonorrhea

Hansen’s disease (leprosy)

Hantavirus infection

Hemolytic uremic syndrome (HUS)

Hepatitis, acute viral (specify type)

Injuries (specify type)

Spinal cord injury

Near drowning

Spotted fever group rickettsioses

Lead, adult elevated blood

Legionellosis

Listeriosis

Lyme disease

Malaria

Meningitis (specify type)

Mumps

Pesticide poisoning, acute occupational

Relapsing fever

Rubella, congenital

Salmonellosis (including typhoid)

Shigellosis

Silicosis

Streptococcal disease, invasive

Syphilis

Tetanus

Trichinosis

Typhus

Vibrio infections

Yersiniosis

In addition, varicella (chickenpox) is reportable by number of cases only, HIV infection in persons 13 years and older is currently reportable by the last four digits of the social security number, and HIV infection in persons less than 13 years of age is reportable by name.

The benefits to be derived from an effective disease surveillance system are substantial, for both the community as a whole and for practicing physicians. Among these benefits:

• Control of disease outbreaks. Prompt reporting is essential to identifying and eliminating sources of infection, whether food-borne, water-borne, vector-borne, and so on.

• Early initiation of prophylaxis.

• Identification of high-risk groups. For example, populations at highest risk of developing AIDS were defined well before the etiology of the disease was understood.

• Identification of emerging infections. The cause and distribution of hantavirus pulmonary syndrome in North America might not have been recognized if not for the astute observations of an individual physician.

• Assessment of vaccine effectiveness.

• Analysis of antimicrobial resistance.

• Measurement of rising and falling trends in disease incidence.

• Identification of unique disease problems within particular regions or counties.

• Providing foundation data for health care planning, policy analysis, and biomedical research.

No disease surveillance system is practical unless it returns information to the community in a usable form. The Texas Department of Health publishes a very wide range of surveillance data through several sources. Epidemiology in Texas Annual Reports are available in printed form from the Bureau of Communicable Disease Control, 1100 W. 49th Street, Austin TX, 78756. Annual Texas Vital Statistics reports are available from the Bureau of Vital Statistics. The Disease Prevention Newsletter and other information is available through the Texas Department of Health website at http://www.tdh.state.tx.us. The CDC publishes national and international surveillance information in Morbidity and Mortality Weekly reports, accessible at http://www.cdc.gov/epo/mmwr/mmwr.html.

Conclusion

A modern disease surveillance system may derive data from a variety of advanced immunologic, molecular, and microscopic techniques, and transmit these data throughout the world instantaneously, but no part of such a system is more important than the contribution made by physicians in promptly reporting notifiable diseases as they are identified. Although the overall significance of a given case of disease is not always immediately obvious, it may prove to be the case that alerts a surveillance worker to a food-borne outbreak, defines the geographical limit of a vector-borne disease, or provides the critical piece of information in an epidemiologic study. Practicing physicians remain the essential part of disease surveillance in Texas.

For more information on reporting procedures or any other aspect of disease surveillance or epidemiology in the state, please call the Infectious Diseases Program at the Texas Department of Health in Austin, at (512) 458-7328, or write:

Richard Campman, Ph.D.
Epidemiology Division
Texas Department of Health
601 W. Sesame Drive
Harlingen, TX 78550