Influenza viruses belong to the family of Orthomyxoviridae and cause ‘the flu’. Influenza A and B viruses (Flu A and Flu B) have a single stranded RNA genome consisting of 8 RNA segments. The genome of Flu A is characterised by a high mutation frequency and so-called “antigenic drift”. Numerous subtypes of Flu A viruses are known. They can be categorised by their surface antigens H (haemagglutinin) and N (neuraminidase), for example Flu A (H1N1) Virus, Flu A (H5N1) Virus. Therefore, yearly in silico analysis of the sequences of newly emerged subtypes is carried out to prevent false negative results arising from primer and/or probe mismatches.
Respiratory syncytial viruses (RSV) are enveloped negative-sense, single stranded RNA viruses of the Pneumoviridae family, genus Orthopneumovirus. RSV are divided into subgroups A and B. RSV infects the lungs and respiratory tract and can cause e.g. bronchiolitis. It is very common and most children have been infected with the virus by the age of two. RSV can also infect adults, however in adults and older, healthy children, the symptoms of RSV infections tend to be mild and typically mimic the common cold. Self-care measures are usually sufficient to manage symptoms discomfort. However, in some cases infection with RSV can be severe, especially in premature babies and infants with underlying health conditions. RSV can also become serious in older adults who suffer comorbidities such as heart and lung disease, or very weak immune systems (immunocompromised).
Coronaviruses (CoV) are a large family of viruses that cause respiratory illness ranging from the common cold to more severe diseases such as Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). The novel Coronavirus (SARS-CoV-2) is a new strain within the Sarbecoviruses that has been identified in humans and causes the pandemic pulmonary disease COVID-19. Common signs of infection include respiratory symptoms, fever, cough, shortness of breath and breathing difficulties, and gastointestinal symptoms including nausea, vomiting, abdominal pain and diarrhoea. In more severe cases, infection can cause pneumonia, severe acute respiratory syndrome, kidney failure and even death.
Such viruses are recognised as having individual pandemic potential and therefore timely detection, differentiation and effective public health strategies are required in order to manage their pathogenicity.