Tuberculosis

Clinical picture

Tuberculosis is an infectious disease caused by the tuberculosis bacterium (Mycobacterium tuberculosis).

The symptoms associated with tuberculosis are often non-specific complaints, which are also associated with many other clinical pictures. This often makes it difficult to recognise the disease. The most common symptoms in the early stages of tuberculosis are: night sweats, fatigue, fever, lack of appetite and consequently often weight loss. People with pulmonary tuberculosis usually have persistent coughing complaints (longer than three weeks) and sometimes cough up some (bloody) mucus. Without proper treatment, however, the patient can become increasingly seriously ill and ultimately even die. It is therefore essential to diagnose and treat tuberculosis in good time.

Additional information from the RIVM.

Infection route

Almost always aerogenic: via small droplets and drop nuclei in the air that can be transmitted over a long distance. Aerosols are spread by coughing, sneezing, laughing and the like, but can also originate from manipulation with infected tissues or organs. The bacteria can survive in drop nuclei for hours and in a pus or sputum container for several days.

Contagious period

A person is considered contagious as soon as they develop coughing complaints. Usually, after 2 weeks of effective treatment, a patient is no longer contagious to the people around them. This does not apply to infections caused by (multi)resistant tubercle bacteria and in severely weakened patients.

Incubation time

8 weeks to lifelong. After an infection, about 10% of the people become ill, 80% of which in the first 2 years. The remaining 20% develop the disease only after a longer period, sometimes spanning several decades.

Potential infectees

All staff who may come occupationally into contact with TB patients or with TB-infected material.

Prevention

Pre-employment examination: Screening for baseline values is usually not required. For reasons of scientific research or because a relatively large number of people are hired from endemic areas, an UMC may opt for a different approach.

Staff who have previously run a high risk must be screened to prevent them from introducing TB unnoticed.

Training: Information must be available to staff, e.g. via a leaflet or the intranet.

General measures: Follow the general guidelines for hygiene and infection prevention. It is important to always wear protective equipment in the event of a risk of coughing and sneezing (scopy, intubation). Wear an FFP2 mask if a patient is infected or suspected of being infected.

Vaccination: BCG vaccination is not indicated in the Netherlands, unless a health care worker works for more than 3 months in an area where TB is endemic. In that case, vaccination is recommended.

PME: in a high-risk department (established through the risk assessment in consultation with the GGD [Area Health Authority]), periodic monitoring for any contamination by means of a tuberculin skin test (Mantoux) or IGRA (Interferon-Gamma Release Assays). Staff who have had BCG vaccination should be checked with IGRA or an X-thorax. In the case of occasional exposure, a contact examination will suffice.

Post-exposure policy

Check with tuberculin skin test/Mantoux): at least 8 weeks after exposure, if possible combined with a baseline measurement within 2 weeks after exposure. If positive, refer to GGD for further examination and, if necessary, prophylaxis. This is an effective intervention to reduce the chance of developing from infection to disease.

Contact examination: in the case of a patient with contagious TB, a contact examination must be carried out among staff members who have had unprotected contact to identify possible infection at an early stage and, if necessary, to initiate prophylaxis. Participation is mandatory. This is done according to the ring principle and under the supervision of the GGD; see information from the RIVM.

Potential infectors

Infected staff. There is an increased risk of TB if a worker:

  • has worked at a microbiological laboratory, pulmonary diseases department, asylum seekers centre or with homeless people, alcohol/drug addicts and/or;
  • comes from Central and Eastern Europe, Asia, Africa, Central and South America.