5. IMMEDIATE ACTION TO BE TAKEN AFTER CLINICAL DIAGNOSIS OF VHF
As soon as the decision is made to proceed on the basis of a presumptive diagnosis of VHF, measures should be applied to minimize exposure of medical staff, other patients and relatives. Whatever is ultimately decided concerning the management of the case, the immediate course of action should be to:
- Inform the management and infection control officers at the medical facility concerned of the existence of the suspected case of VHF.
- Isolate the patient and apply infection precautions as best as can be managed under the circumstances in cooperation with infection control staff (see section 6.3).
- The precautions must remain in force until the possibility of VHF has been excluded or the patient is no longer under care at the facility concerned.
- Administer such life-saving therapy as may be necessary and possible, e.g. blood/fluid therapy.
- Take steps to verify the diagnosis (see sections 4.3).
- Cooperate with infection control officers in preparing a list of staff members who have had contact with the patient or fomites, including ambulance, laboratory and cleaning personnel - the contacts must be informed of the risks and precautions to be taken, and placed under observation (see section 7 for definitions of exposure, contact and observation).
- Notify the National Director of Communicable Disease Control (CDC) and the relevant Provincial Coordinator of CDC of the existence of the suspected case of VHF so that they can investigate the circumstances surrounding the incident, place relatives and cohorts and other contacts of the patient/s under observation if indicated, and take necessary actions to control any potential outbreak of VHF in the community at large (see section 7.2 for contact details of the officials).
- Decide whether the patient is to be retained at the primary hospital, or whether to seek transfer to a hospital more suited to managing the case. Decisions to transfer VHF patients cannot be taken unilaterally; see section 7.1 for the criteria and mechanisms for reaching decisions on referral.
- Assess the status of the patient as either low, moderate or high risk with respect to the probability that VHF is involved, the likely outcome of the disease, and the feasibility of safe transfer - sometimes the process of transfer poses too great a threat to the life of the patient or the safety of the personnel involved:
Low risk patients
This category has febrile disease with features suggestive of VHF (e.g. thrombocytopenia), but are not necessarily severely ill and lack a history of contact with known VHF patients or animals (other than long-term pets), or animal tissues, or ticks and mosquitoes, and have not left an urban environment for at least 3 weeks prior to onset of illness. There are no haemorrhages, and risk of spread of infection is assessed as low.
Moderate risk patients
This category has febrile disease with features suggestive of VHF, and are not necessarily severely ill, but have visited or resided in a tropical or rural environment, or have had contact with animals or animal tissues, or ticks and mosquitoes during the 3 weeks preceding onset of illness. They have not had direct contact with known VHF patients or fomites (see section 7.3) but may have an indirect association with such patients, e.g. they have worked, resided in or visited the same places as VHF patients. Although there may be no haemorrhages, it is assessed that infection with a VHF agent may be involved.
This category is severely ill with fever and haemorrhagic manifestations (this criterion is sufficient to place patients in the high risk category). In addition, they may have visited or resided in a tropical or rural environment, or have had contact with animals, animal tissues or ticks and mosquitoes during the 3 weeks preceding onset of illness. Alternatively, they may not necessarily be severely ill, but have had definite exposure to VHF (see section 7.3). This includes a) hospital and laboratory staff who have developed illness within 3 weeks* of last known contact with a confirmed VHF patient or fomites associated with such patients, and b) relatives and close associates of known VHF patients. (*The interval is 2 weeks for arbovirus diseases such as Congo fever, but 3 weeks for Lassa, Marburg and Ebola haemorrhagic fevers.)