The top tweeted terms are the trending industry discussions happening on Twitter by key individuals (influencers) as tracked by the platform.

1. Covid-19 – 8,509 mentions

Airborne transmission of coronavirus, face masks protecting against coronavirus and studies demonstrating presence of Covid-19 antibodies in recovered patients were popularly discussed in the fourth quarter of 2020. According to an article shared by Ian M Mackay, a virologist, airborne transmission plays a major role in the spread of coronavirus as acknowledged by the US Centers for Disease Control and Prevention (CDC).

The CDC noted that under certain conditions droplets and particles remain in the air for several hours. The transmission is more prominent within enclosed spaces that have poor ventilation, which can lead to build-up of virus-carrying particles. Although there was evidence of airborne transmission of the virus, this is the first time that the CDC has acknowledged the possibility.

Carlos del Rio, a professor of medicine at Emory University School of Medicine, further shared an article on how face coverings or a protective cloth face masks can save lives during the Covid-19 pandemic. Several studies have shown that face masks can reduce the transmission of the virus or even reduce the severity of the infection in case a person contracts the virus. Although N95 masks are considered the most effective, some studies have shown that surgical and cloth masks are 67% effective in offering protection against the virus.

Covid-19 was also discussed by Francis Collins, director of the National Institutes of Health, on two studies demonstrating the presence of Covid-19 antibodies in recovered patients. In one of the two studies, the researchers tested the development of three different types of antibodies in the blood samples after 12 days of infection. The researchers found that the SARS-CoV-2 antibodies were present in some patients for up to four months.

2. HIV – 1,811 mentions

The failure of a large-scale human immunodeficiency virus (HIV) vaccine trial, a single shot being more effective in preventing HIV than daily pill and approval of ViiV Healthcare’s Vocabria for treatment of HIV were the most popular discussions in Q4 2020. According to an article shared by Matthew Hodson, executive director of charity organisation NAM Aidsmap, the failure of the first large-scale HIV efficacy vaccine trial, HVTN 702 (Uhambo), is a wake-up call for southern Africa.

The vaccine was ineffective as there was no difference in the rate of HIV infection between those receiving the vaccine and those receiving placebo. Out of the 5,407 women recruited from South Africa, 123 women in the placebo group and 129 women in the vaccine group caught HIV indicating the high incidence of the disease in the country, the article noted.

Ludo Bok, team leader at United Nations Development Programme, further, shared an article on how a single shot of a drug developed by ViiV Healthcare has proven to be more effective than a daily pill in preventing HIV in women in a clinical trial. Conducted by the H.I.V. Prevention Trials Network, the trial recruited 3,223 participants in 20 sites across seven countries in Africa.

The trial compared the efficacy of the injected drug known as cabotegravir with Truvada, the only approved preventive drug for HIV. A total of 34 women who received Truvada became infected with HIV compared to four of the women who received cabotegravir. The researchers ended the trial early as cabotegravir proved to be 89% more effective than Truvada.

Discussions on HIV also included an article tweeted by Ani Shakarishvili, a physician, on authorisation of REKAMBYS (rilpivirine) in combination with ViiV Healthcare’s Vocabria (cabotegravir) in the European Union for the treatment of HIV-1 infection in adults who are virologically suppressed. The combination treatment is the first long-acting injectable treatment to be approved for HIV patients in Europe and eliminates the need for daily oral tablets.

3. Hepatitis C – 141 mentions

Direct-acting antivirals (DAAs) reducing incidence of hepatitis C virus (HCV) infections and Opt Out testing for blood-borne viruses (BBVs) were widely discussed in the fourth quarter of 2020. Carlos del Rio shared a study on the impact of unrestricted access to DAAs on incidence of HCV infections in the Netherlands. The retrospective cohort study was conducted in 23,590 individuals without previous HCV infection. The incidence of HCV infection reduced from 55.6 per 1000 person-years between 2006 and 2015 to 11.4 per 1000 person-years in 2019 indicating that unrestricted access to DAAs significantly reduced infection rates.

Hepatitis C also trended in discussions around opt out testing for BBVs such as HCV and HIV, according to an article shared by Dr Steve Taylor, a researcher. Opt out testing is the only way to normalise HIV and HCV as it reduces much of the associated stigmas. Intimating patients regarding a HIV or HCV test and providing them with an option to decline has helped in yielding higher testing rates, the article highlighted.

4. Tuberculosis – 136 mentions

The impact of higher costs on tuberculosis prevention treatment, shortening of tuberculosis treatment duration, TB incidence in migrants were popularly discussed topics in the last quarter of 2020. According to a study shared by infectious disease epidemiologist Steffanie Strathdee, the effective delivery and completion of tuberculosis preventive care is necessary for the elimination of the disease. Higher medical costs, however, leads to incomplete treatment.

The study compared the cost of isoniazid daily treatment for six months (6H) with three months weekly treatment with isoniazid and rifapentine (3HP) for tuberculosis prevention in a high-burden environment between October 2016 and February 2018. The study found that the cost of 3HP was much lower with higher treatment completion rates.

Matthew Hodson, further, shared an article on how the six-month standard of care tuberculosis treatment can be shortened to four months by just replacing two drugs with newer agents such as high dose rifapentine and moxifloxacin. The study conducted by CDC’s Tuberculosis Trials Consortium showed that a shorter treatment regimen will improve adherence and reduce costs for the healthcare system.

Tuberculosis also trended with regards to increase in proportion of cases among European migrants. A cross-sectional secondary database analysis was performed using data from 23 years between 1995 and 2017. The study calculated the number of extrapulmonary tuberculosis cases between migrants (25.7%) and non-migrants (74.3%). The results from the study showed that extrapulmonary tuberculosis was much more common in migrants than in non-migrants. Clinical awareness and screening programmes were essential to detect tuberculosis cases, the article detailed.

5. Remdesivir – 90 mentions

World Health Organization (WHO) recommending against use of remdesivir for hospitalised patients with Covid-19 and the drug speeding up recovery from Covid-19 were widely discussed topics in the fourth quarter of 2020. According to an article shared by Dr Saskia Popescu, an infectious disease epidemiologist, the WHO advised against the use of remdesivir in treating hospitalised patients infected with coronavirus.

The WHO made the decision following results from the Solidarity Trial, which showed that remdesivir did not improve survival rates or reduce the need for ventilation in Covid-19 patients. The announcement came as a set back to the drug, which was widely acknowledged as a treatment for Covid-19, the article noted.

Amesh Adalja, an infectious diseases specialist, further shared an article on how remdesivir helped in speedy recovery of hospitalised Covid-19 patients. People recovered from the virus in an average of ten days compared to 15 days for those receiving only supportive treatment such as oxygen and IV fluids. The article noted that remdesivir protects against Covid-19 by hindering the ability of the coronavirus to replicate within human cells.