Doxycycline as an antimalarial: Impact on travellers' diarrhoea and doxycycline resistance among various stool bacteria - Prospective study and literature review

Doxycycline inhibits neurotropic enterovirus proliferation in vitro

Human enteroviruses (EVs) represent a global public health concern due to their association with a range of serious pediatric illnesses. Despite the high morbidity and mortality exerted by EVs, no broad-spectrum antivirals are currently available. Herein, we presented evidence that doxycycline can inhibit in vitro replication of various neurotropic EVs, including enterovirus A71 (EV-A71), enterovirus D68 (EV-D68), and coxsackievirus (CV)-A6, in a dose-dependent manner. Further investigations indicated that the drug primarily acted at the post-entry stage of virus infection in vitro, with inhibitory effects reaching up to 89 % for EV-A71 when administered two hours post-infection. These findings provide valuable insights for the development of antiviral drugs against EV infections.

Experience with dalbavancin use in various gram-positive infections within Aberdeen Royal Infirmary OPAT service

PURPOSE

Dalbavancin, approved in 2014 for Gram-positive acute bacterial skin and skin structure infections (ABSSSI), has pharmacokinetics enabling treatment with one or two doses. Dalbavancin might be useful in outpatient parenteral antibiotic therapy (OPAT) of deep-seated infections, otherwise requiring inpatient admission. We documented our experience with pragmatic dalbavancin use to assess its effectiveness for varied indications, on- and off-label, as primary or sequential consolidation therapy.

METHODS

Patients prescribed dalbavancin between 1 December 2021 and 1 October 2022 were screened for demographics of age, sex, Charlson comorbidity index (CCI), allergies, pathogens, doses of dalbavancin, other antibiotics administered and surgery. Where available, infection markers were recorded. The primary outcome was a cure at the end of treatment. Secondary outcomes included any adverse events and for those with treatment failures, response to salvage antibiotics.

RESULTS

Sixty-seven per cent of patients were cured. Cure rates by indication were 93% for ABSSSI, 100% for bacteraemia, 90% for acute osteomyelitis, 0% for chronic osteomyelitis, 75% for native joint septic arthritis and 33% for prosthetic joint infection. Most bone and joint infections that were not cured did not have source control, and the goal of treatment was suppressive. Successful suppression rates were greater at 48% for chronic osteomyelitis and 66% for prosthetic joint infections. Adverse events occurred in 14 of 102 patients.

CONCLUSION

This report adds to clinical experience with dalbavancin for off-label indications whilst further validating its role in ABSSSI. Dalbavancin as primary therapy in deep-seated infections merits investigation in formal clinical trials.

Already current practice? A snapshot survey on doxycycline use for prevention of sexually transmitted infections in parts of the German MSM community

PURPOSE

Recent studies point toward a potential benefit of doxycycline use for post-exposure prophylaxis (PEP) or pre-exposure prophylaxis (PrEP) to prevent sexually transmitted infections (STIs). Although prescribing doxycycline in a prophylactic intention is not generally recommended yet, we noticed an increasing number of inquiries from individuals within the LGBTQ community for doxycycline prescriptions.

METHODS

We conducted an anonymous online survey to evaluate the current extent of doxycycline use for PEP or PrEP within the LGBTQ community using REDCap electronic data capture tools. Participants gained access to the online survey through a QR code on posters in the premises of our STI outpatient department and at LGBTQ community-related events in the south-western region of Germany. Additional access was provided by a direct link shared on social media profiles for men having sex with men (MSM), transgender, and queers.

RESULTS

96 of 99 responses were eligible for analysis. Twenty-two participants (23%) indicated to have already used doxycycline for PEP and six participants (6%) used doxycycline for PrEP. The majority of participants used pills left over from previous doxycycline treatment. Forty percent of indicated modes of access were without a regular prescription, e.g., by provision from acquaintances (with or without healthcare profession) or by ordering online.

CONCLUSION

Our study shows that the concept of doxycycline use for prevention of STIs is already well known and applied in the LGBTQ community. Further analysis, especially modeling studies, are needed to evaluate strategies aiming to reduce doxycycline intake (PEP/PrEP versus repeated targeted therapies) and improve sexual health outcomes within the community.