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CPD ACTIVITY
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RET AIL PHARMA C Y • MA Y 2020
Combination products, containing antihistamines,
decongestants and/or analgesics, are also available
OTC but the evidence for their effectiveness is limited.47
Analgesics, such as aspirin, paracetamol and ibuprofen,
are also available for treatment of common cold symptoms
such as headache, fever, sore throat, pain and myalgia.48
Reviews on the safety and efficacy of OTC analgesics provide
an excellent source of information on treatment of pain and
fever, but little specific information on the role of analgesics in
treating the symptoms of URTIs.49 Despite the widespread use
of these products, it’s interesting to note that no convincing
case can be made for combination products in treatment of
the symptoms of URTIs.49 Reviewed studies paint a picture
of concern over the risk benefit ratio for use of analgesics in
treatment of URTI symptoms.50
Implications for pharmacy practice
This review considers illness presentations in pharmacy,
providing distinct features to aid pharmacists in decision
making during consultation. Although the differences in clinical
presentation are not so useful in identifying the causative
agent of an URTI, interest has been mounting to improve the
accuracy of symptomatic diagnosis in community pharmacy.
Early diagnosis and referral are critical for any antiviral
therapy, and for the initiation of public health measures such
as isolating infected cases. There is uncertainty regarding the
efficacy and safety of interventions for preventing the common
cold in healthy people. The independent effectiveness of
measures to ‘increase social distance’ and wearing masks in
public places requires further evaluation.6
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Table 3.
Emerging viral infections.
Virus
Determinants of interspecies transmission
Comment on public health interventions
Chikungunya virus
A mosquito-transmitted alphavirus that is maintained between
non-human primates, small mammals (such as bats) and Aedes
mosquitoes (vector). Transmission to humans occurs through
mosquito bite.
Previous cases involved infected travellers to Australia.
Symptoms include fevers, rigors, headache, arthralgia, and rash.
Prevention is based on insect control and in avoiding mosquito
bites. The known vectors are present in Australia, so it may be of
importance that infected travellers be identified and isolated from
mosquito exposure early in their illness. No local transmission has
been reported in Australia. 24-26
Ebola virus
Bats are believed to be the primary reservoir of Ebola virus.
Transmission to humans is believed to occur mainly through
‘bushmeat’ activities (capture and slaughtering of wild animals,
including non-human primates, which are thought to be vectors in
transmission to humans).
Control measures include identification, isolation and care of
suspected patients, strict infection prevention and control among
those caring for patients, and hygiene during burials. 27-29
Hendra virus
The virus is transmitted to horses by flying foxes
Pteropus
species,
which are the reservoir hosts.
It is believed that the most likely route is ingestion by horses of
pasture or feed contaminated with the urine, faeces, saliva or birthing
products from infected flying foxes, with human infection resulting
from direct contact with infected horses. There is no evidence of
human-to-human transmission.
Hendra virus infection in humans is a fatal disease characterised by
influenza-like illness, with neurological symptoms, then pneumonia.
The disease could theoretically occur anywhere in Australia where
there are flying foxes. Cats and dogs are included in surveillance
because they have been shown to be susceptible to experimental
infection with the virus.
Hygiene is recommended as there is no effective treatment
or vaccination. 30, 31
Middle East
respiratory
syndrome virus
(MERS)
Origin of MERS-CoV is believed to be an animal disease with
subsequent transmission to humans.
It infects multiple species, including bats, dromedary camels and
European hedgehogs (
Erinaceus europaeus
). Humans become
infected through close contact with the host species.
Super-spreading events occur according to the Pareto principle,
in which 20 per cent of the infected population transmit the disease
to the other 80 per cent of the population.
Public health strategies include screening and vaccinating
susceptible animal species.32-34
Nipah virus
Natural reservoir for Nipah virus (NiV) is fruit bat (flying foxes) of the
Pteropus
species in Australia. NiV infection in people demonstrates
spillover of the virus from its natural hosts to livestock (pigs), and
subsequent transmission to other animal hosts, including humans
Human-to-human transmission has been observed.
The clinical manifestations of acute NiV infection range from fever
and mild headache to a severe acute encephalitic syndrome in which
there is a high mortality. Much remains to be understood about this
newly emerging zoonosis.35-37
Ross River virus
(RRV)
An arthropod-borne alphavirus.
Aedes vigilax
mosquito is the vector.
The virus is maintained in nature via transmission cycles between
arthropods vectors and vertebrate hosts, including humans.
RRV is endemic to Australia. Climate variability is thought to
contribute to the RRV transmission in recent years.
In most cases the onset is abrupt, with chills and joint and
muscular pain. Fever is usually mild. Incapacity occurs due to
generalised polyarthritis. 38,39
Severe acute
respiratory
syndrome virus
(SARS)
A coronavirus that has an established potential for cross-species
transmission within domestic animals.
Suddenly escaped to become the highly pathogenic human SARS-
CoV strain from zoonotic reservoirs (palm civets and racoon dogs).
Bats (
Rhinolophus
genus) are recognised as natural hosts.
Believed to spread by droplet transmission or direct person to person
through close contact.
Public health efforts to identify and isolate infected persons,
monitor or quarantine their contacts, and strengthen infection
control in healthcare settings. 40-42
Zika virus (ZKV)
A mosquito-borne flavivirus related to yellow fever virus, dengue
virus, and West Nile virus.
Transmitted by many
Aedes spp.
mosquitoes.
Worldwide, only sporadic ZKV infections have been reported since
discovery of the virus in 1947.
The knowledge of sylvatic (wild not domesticated) species’
competence (both vectors and hosts) to transmit ZKV is still limited.
Clinical presentation in humans is often mild or asymptomatic.
Zika is the cause of neurological malformations in newborns,
including microcephaly.
Recent travel to an endemic region may be suggestive. 43-45