Antibiotic prescribing in Covid
Although antibiotics are not indicated for Covid-19, as it can be difficult to distinguish from, or co-present with, bacterial pneumonia, many patients will ultimately end up receiving them.
In a retrospective study of 191 patients who were diagnosed with Covid in the early stage of the pandemic in Wuhan, China, 50% of those who died developed a secondary bacterial infection (although the paper is not clear on what basis e.g. microbiological or clinical this diagnosis was made). Bacterial infection tended to occur late on in the disease course, at median day 17 from symptom onset. In comparison only 15% of survivors were diagnosed with secondary infection.
NICE guidelines do not recommend routinely prescribing antibiotics in Covid-19 infection:
As COVID‑19 pneumonia is caused by a virus, antibiotics are ineffective.
4.6 Do not offer an antibiotic for treatment or prevention of pneumonia if:
- COVID‑19 is likely to be the cause and
- symptoms are mild.
Inappropriate antibiotic use may reduce availability if used indiscriminately, and broad-spectrum antibiotics in particular may lead to Clostridioides difficile infection and antimicrobial resistance.
4.7 Offer an oral antibiotic for treatment of pneumonia in people who can or wish to be treated in the community if:
- the likely cause is bacterial or
- it is unclear whether the cause is bacterial or viral and symptoms are more concerning or
- they are at high risk of complications because, for example, they are older or frail, or have a pre-existing comorbidity such as immunosuppression or significant heart or lung disease (for example bronchiectasis or COPD), or have a history of severe illness following previous lung infection.
4.8 When starting antibiotic treatment, the first-choice oral antibiotic is:
- doxycycline 200 mg on the first day, then 100 mg once a day for 5 days in total (not in pregnancy)
- alternative: amoxicillin 500 mg 3 times a day for 5 days.
4.9 Do not routinely use dual antibiotics.
4.10 For choice of antibiotics in penicillin allergy, pregnancy and more severe disease, or if atypical pathogens are likely, see the recommendations on choice of antibiotic in the NICE antimicrobial prescribing guideline on community-acquired pneumonia.
4.11 Start antibiotic treatment as soon as possible, taking into account any different methods needed to deliver medicines to patients during the COVID‑19 pandemic (see recommendation 1.3).
However, in severely unwell patients with possible Covid-19 infection, WHO recommends commencing empirical antibiotic therapy according to local/national policy within 1 hour. Antibiotic therapy should be rapidly stepped down following access to microbiology results or as the clinical diagnosis becomes clear.
If there is known seasonal influenza circulation then neuraminidase inhibitors e.g. oseltamivir can be commenced empirically then stopped once a respiratory virus PCR panel e.g. from a nose/throat swab is available. These should not be routinely prescribed.