Viral haemorrhagic fevers (VHFs)

Viral haemorrhagic fevers (VHFs)
Viral haemorrhagic fevers (VHFs) are imported infections caused by a range of viruses. VHF
infection is uncommon but is important because it is difficult to diagnose, has a high casefatality
rate with no effective treatment and it can spread rapidly within the hospital setting
unless correct precautions are taken. All units admitting returning travellers should have
policies in place to risk assess and identify possible cases. Standard principles of infection
control should be used while the assessment is carried out. Following the assessment, the
patient is categorised as one of the following: highly unlikely to have VHF, possibility of VHF,
high possibility of VHF or confirmed VHF. Further management, including the level of infection
control precautions, depends on the outcome of the risk assessment. Always inform
the Infection Prevention and Control Team and a consultant microbiologist of any suspected
case of VHF. VHF is a notifiable disease: notify high possibility/confirmed cases
urgently.
SPREAD B Y
• Direct contact – if blood or body fluids come into contact with broken skin or mucous
membranes.
• Indirect contact – with an environment contaminated with splashes or droplets of blood
or body fluids.
I N F E C T I O U S P E R I OD The incubation period ranges from 3 to 21 days. The patient is
considered potentially infectious until an alternative diagnosis is confirmed or until there
has been a negative VHF screen and the patient has been afebrile for 24 hours. If VHF is the
confirmed diagnosis, the patient is considered infectious for an indefinite period (seek
expert guidance).
I N F E C T I O N C O N T R O L P R E C A U T I O N S
For patient highly unlikely to have VHF (no risk/ minimal risk)
1 Isolation Not required
2 Hand washing Required
3 Gloves Required
4 Apron Required
5 Mask Not required
6 Eye protection Not required
If possibility of VHF
1 Isolation Required. Should have dedicated en suite facilities
or dedicated commode
2 Hand washing Required
3 Gloves Required
4 Apron Required
5 Mask Not generally required, but if patient is bruising or
bleeding wear a fluid-repellent surgical facemask
for routine care and FFP3 mask for aerosol- or
splash-generating procedures
6 Eye protection Not generally required, but disposable visor
recommended if patient is bruising or bleeding

164 VIRAL HAEMORRHAGIC FEVERS (VHFs)
For high possibility of VHF in a stable patient
1 Isolation Required. Should have dedicated en suite facilities
or dedicated commode
2 Hand washing Required
3 Gloves Required
4 Apron Required
5 Mask Required: fluid-repellent surgical mask generally
adequate, FFP3 mask for aerosol- or splashgenerating
procedures
6 Eye protection Required – disposable visor
For high possibility of VHF in patient with bruising, bleeding or uncontrolled diarrhoea/
vomiting
1 Isolation Required. Should have dedicated en
suite facilities or dedicated commode
2 Hand washing Required
3 Gloves Double gloves required
4 Apron Fluid-repellent disposable gown
required
5 Mask FFP3 mask required
6 Eye protection Disposable visor required
EQUIPMENT Equipment used in high-possibility/confirmed cases of VHF should be
single
use and disposable.
S TA F F If there is a high possibility of VHF, or a confirmed case, the number of staff caring
for the patient should be restricted to essential staff only and a record of these staff should
be kept. Remember to inform the laboratory of a suspected case of VHF so that laboratory
staff can take appropriate precautions when handling specimens.
VI S I T O R S Visitors should not be allowed if there is a high possibility or confirmed case
of VHF.
PAT I E N T T R A N S F E R Patient transfer should not take place unless absolutely essential
for medical reasons. The receiving department should be informed in advance of the possibility
of VHF. The Infection Prevention and Control Team should also be informed of any
planned patient movement.
MORE INFORMAT I O N Symptoms include fever, sore throat, headache, muscle or joint
pain, diarrhoea and vomiting. Obvious bleeding occurs at a late stage of the illness. Cases
of VHF are rare in the United Kingdom and are always imported from other countries. Any
patient with high-possibility VHF, or with possible VHF with bruising or bleeding, must be
discussed with an infectious disease unit. Any patient with confirmed VHF must be transferred
to a high-security infectious disease unit. Management of a confirmed VHF case is a
highly specialist subject and is not within the scope of this book
Whooping cough
Whooping cough is a respiratory infection caused by the bacterium Bordetella pertussis.
Whooping cough is a notifiable disease.
SPREAD B Y Close direct contact with an infected person, by droplet spread. It is highly
contagious – up to 90% of susceptible household contacts will develop the disease.
I N F E C T I O U S P E R I OD The incubation period is usually 7–10 days (rarely it can be up
to 21 days). The infectious period is up to 3 weeks after the onset of symptoms. Beyond
3 weeks, risk of transmission of infection is minimal, even if the cough persists.
I N F E C T I O U S C O N T R O L P R E C A U T I O N S
1 Isolation Required
2 Hand washing Required
3 Gloves Required
4 Apron Required
5 Mask Required
6 Eye protection Not required
The risk of transmission is minimal after 3 weeks of illness, but in a few cases (up to 20%)
infectivity can persist for up to 6 weeks. Therefore the above infection control precautions
should be taken in all hospitalised cases. Discuss with your Infection Prevention and Control
Team if required.
S TA F F All staff looking after a patient with whooping cough should have had a full
course of whooping cough vaccination. If vaccination history is incomplete or unknown,
arrange for other staff to care for the patient and discuss with Occupational Health.
VI S I T O R S Visitors should be kept to a minimum number and should be limited to adults
with a history of vaccination against whooping cough. Children under the age of 1 year
should not visit under any circumstances. Visitors should comply with all above
precautions.
PAT I E N T T R A N S F E R Patient transfer should be kept to a minimum. The patient should
wear a mask during transfer. The receiving ward/department should be informed in advance
of the diagnosis.
MORE INFORMAT I O N Whooping cough may occur at any age. Young infants are
the most at risk because they are not yet vaccinated and because infection at this age can
cause severe illness with breathing difficulties.
Epidemics of whooping cough occur every 3 to 4 years, and the highest number of cases
is usually in July–September annually.
Whooping cough is a vaccine-preventable disease. In the UK it is given as part of the
routine childhood immunisation programme and is also given to high-risk groups as
needed, e.g. to pregnant women during the 2012–2013 national outbreak. Immunity
wanes over time and it is possible to catch whooping cough even if you have previously had
the illness or a course of vaccinations.
The illness begins with coryzal symptoms and progresses to a dry cough, which may
occur in paroxysms (outbursts of coughing) and may end with vomiting or with an intake

of air, which makes a ‘whooping’ sound. The cough may go on for weeks or months.
Whooping cough is treated with antibiotics (usually erythromycin, clarithromycin or
azithromycin) within the first 3 weeks of symptoms. Treatment is not necessary later in the
course of the illness. Treatment duration used to be 14 days but has now been reduced
to 7 days (3 days if taking azithromycin). Unvaccinated/partially vaccinated cases up to
10 years of age should complete their course of primary immunisation and booster vaccine
once they have recovered from their acute illness.
Contacts of cases may be offered antibiotic prophylaxis and/or vaccination if identified
promptly.
Laboratory confirmation is possible by culture or PCR of pernasal swab or nasopharyngeal
aspirate, or by serology. Discuss with your microbiologist or Health Protection Unit to

ascertain the most appropriate test.