Study: Higher risk of accompanying bacterial infections with flu, RSV than SARS-CoV-2
A recent study conducted in Ontario revealed that individuals infected with influenza and respiratory syncytial virus (RSV) have a greater incidence and risk of simultaneous bacterial infections than those infected with SARS-CoV-2. This finding was reported by researchers this week in the journal Open Forum Infectious Diseases.
However, the likelihood of bacterial infections in COVID-19 patients significantly increased after 48 hours when compared to other viruses.
A team of researchers from the Institute for Clinical Evaluative Sciences in Toronto used data from the Ontario Laboratories Information System to study the occurrence of bacterial infections alongside laboratory-confirmed cases of influenza A and B (FLUA and FLUB) and RSV between 2017 and 2019, as well as SARS-CoV-2 cases from 2020 to 2021. They also looked into whether certain risk factors, such as patient demographics, are linked to varying chances of having a concurrent bacterial infection. These infections were categorized as coinfections (occurring 2 days before to 2 days after the viral infection) and secondary infections (happening more than 2 days after the viral infection).
During the study, out of 885,004 respiratory viral infections, 4,230 cases (or 0.5%) had simultaneous bacterial infections. Specifically, this occurred in 422 out of 8,891 patients with FLUB (4.7%), 861 out of 22,313 FLUA patients (3.9%), 428 out of 12,744 RSV patients (3.4%), and 2,519 out of 841,026 COVID-19 patients (0.3%). The most common bacteria identified in these co-infections were Staphylococcus aureus, Streptococcus pyogenes, and Pseudomonas aeruginosa.
Increased Risk Of Secondary Infections From SARS-CoV-2
After accounting for various factors, the likelihood of bacterial infection was found to be 1.69 (with a 95% Confidence Interval of 1.48 to 1.93) for FLUA, 2.30 (95% CI, 1.97 to 2.69) for FLUB, and 1.56 (95% CI, 1.33 to 1.82) for RSV when compared to SARS-CoV-2. A deeper analysis showed that while the adjusted chances of having a bacterial co-infection were lower for those infected with SARS-CoV-2, the chances of developing a secondary bacterial infection were higher for SARS-CoV-2 than for FLUA, FLUB, and RSV.
The researchers indicate that the results have significant consequences for managing the use of antibiotics.
"They pointed out that prescribing antimicrobial medications is frequent among COVID-19 patients, which could contribute to increased antimicrobial resistance issues. However, they argue that starting these medications early in patients who are not severely ill isn't warranted due to the low likelihood of co-infections. These insights should guide careful prescribing practices for individuals with suspected or confirmed cases of COVID-19."
Mpox Spreads In Africa: Clade 1b Found In 2 More Countries
The number of mpox cases in Africa continues to rise, with an increase in both infections and fatalities reported last week compared to the week before. This was announced today by the director of the Africa Centres for Disease Control and Prevention (Africa CDC) during their weekly update.
Countries have confirmed an additional 36 fatalities, bringing this year's total to 1,200. "We continue to lose lives," stated Jean Kaseya, MD, MPH, the director-general of Africa CDC. The region saw 2,708 new infections, leading to an overall figure of 62,171 cases across 20 nations so far this year. The majority of these cases, along with all recent deaths, were reported in the Democratic Republic of the Congo (DRC), which remains the primary center of the outbreak.
Kaseya announced that genetic sequencing from two recently impacted nations—Zimbabwe and Zambia—has identified the new clade 1b virus for the first time in those areas. Generally, clade 2 viruses primarily target adults, while the older clade 1a virus is significantly impacting children. For instance, in the Democratic Republic of the Congo (DRC), a staggering 87.6% of individuals infected with clade 1a are children. In contrast, the new clade 1b virus is affecting both young and older populations.
Diverse Clade Outbreaks: A Complex Challenge
Kids under 15 account for 34.2% of confirmed cases, with females making up over half of these cases at 54.2%. The area has been dealing with complicated outbreaks featuring various strains of the virus and differing spread patterns. Some countries, like the DRC, show distinct regional differences in how the virus is affecting their populations.
We're continuing to lose individuals.
Kaseya mentioned that the area is still facing challenges with lab testing, and steps are being taken to distribute testing capabilities more widely. When samples are sent to farther labs, it can negatively affect their quality, leading to less accurate test results.
In the Democratic Republic of Congo, authorities are observing similar patterns with mpox and measles, particularly in the Equateur and Tshuapa regions. Kaseya noted that the increased monitoring of mpox might also be unintentionally helping to identify measles cases more effectively, or the trends could be influenced by the similarities in how both diseases are defined.
California H5N1 Outbreaks Exceed 500 Cases
The Animal and Plant Health Inspection Service (APHIS) of the US Department of Agriculture (USDA) announced today the detection of 11 additional H5N1 avian flu outbreaks in dairy cows, all occurring in California. With these new cases, California's overall count reaches 504, while the nationwide total rises to 718 across 15 states.
California leads the nation in dairy production, boasting about 1,300 commercial herds. The outbreaks started in late August and have since impacted nearly 40% of the state's dairy cattle.
APHIS also reported additional cases of avian influenza in poultry across three states. In California, which has faced significant outbreaks in both cattle and poultry, the virus was detected at a commercial turkey farm in Sacramento County that houses over 61,000 birds. Furthermore, new cases were confirmed at two commercial farms in Stanislaus County, one of which is a turkey producer and the other a facility raising laying hens.
Cases were also noted in small poultry groups in Riverside County, California, Douglas County, Kansas, and Utah County, Utah.
Recombinant Pertussis Vaccine Gives 5-Year Protection
Researchers found that protection against pertussis (whooping cough) lasted for five years after adolescents and young adults received a recombinant vaccine. They believe this discovery supports the idea of using it as a booster for young people.
This study revisited individuals who were vaccinated five years prior, when they were between 12 and 17 years old. They had received a recombinant acellular pertussis vaccine during a phase 2/3 randomized clinical trial that took place in Thailand from July 2015 to November 2016. As infants, these participants had been given three doses of the whole-cell pertussis vaccine.
Out of 159 participants, 55 were given the pertussis-only vaccine (aPgen), 52 received the tetanus-diphtheria-pertussis vaccine (TdaPgen), and another 52 received the Tdapchem booster shot.
The researchers gathered blood samples from all participants to assess the levels of serum PT-immunoglobulin G (IgG) and filamentous hemagglutinin (FHA)-IgG antibodies. Additionally, they measured the titers of pertussis toxin (PT) neutralizing antibodies in 55 individuals who received the aPgen vaccine. The concentration of antibodies was evaluated using enzyme-linked immunosorbent assay (ELISA) and assays involving Chinese hamster ovary cells.
The authors stated, "Pertussis toxin (PT), especially when genetically modified to remove its toxic effects (PTgen), is the key component that provides protection against whooping cough. Our earlier research showed that recombinant acellular pertussis vaccines containing PTgen produce a stronger immune response and generate much higher levels of PT-neutralizing antibodies in teenagers compared to the chemically inactivated tetanus-diphtheria-pertussis booster vaccines (Tdapchem)."
The findings were released today in JAMA Network Open.
Study Shows Boosters Benefit Teens And Adults
Five years after receiving the vaccine, the levels of neutralizing anti-PT antibodies were over four times higher than the minimum threshold of 5 international units per milliliter (IU/mL). The concentration of PT neutralizing antibodies was 2.5 times greater for those who received the aPgen vaccine and three times higher for TdaPgen compared to their pre-vaccination levels. Additionally, 75% of individuals who received the aPgen vaccine had PT-IgG antibody levels exceeding 20 IU/mL, while 56% of TdaPgen recipients reached this level. In contrast, only 27% of those who received the Tdapchem vaccine had PT-IgG levels above 20 IU/mL.
The authors noted, "Earlier studies showed that vaccines containing PTgen, which are genetically modified for safety, provided lasting protection after initial vaccinations in infants. Our results indicate that these PTgen vaccines may also provide extended protection in teenagers, making them suitable as booster shots for both adolescents and adults to improve community immunity."
WHO Approves Rapid Molecular TB Test
Today, the World Health Organization (WHO) announced that it has given prequalification approval to a quick molecular test for tuberculosis (TB).
The Xpert MTB/RIF Ultra test is a type of nucleic acid amplification test that finds the genetic material of Mycobacterium tuberculosis in sputum samples and delivers results in just a few hours. Additionally, it can spot mutations linked to rifampicin resistance, an important factor in identifying multidrug-resistant tuberculosis.
The WHO prequalification process includes testing products, assessing their performance, inspecting production facilities, and undertaking various activities to guarantee that countries can access essential health products that adhere to international quality, safety, and effectiveness standards. The evaluation for the prequalification of Xpert MTB/RIF Ultra was conducted by the WHO based on details provided by the manufacturer, Cepheid Inc., which were reviewed by the Health Sciences Authority of Singapore.
This test is the inaugural examination for diagnosing tuberculosis that complies with the WHO's prequalification criteria. Representatives from the World Health Organization emphasize that identifying tuberculosis accurately and promptly, especially drug-resistant forms, is a critical global health concern.
"The initial prequalification of a tuberculosis diagnostic test signifies an important step in the World Health Organization's mission to help nations enhance their access to effective TB testing methods that align with WHO guidelines and adhere to strict standards for quality, safety, and performance," stated Yukiko Nakatani, MD, PhD, WHO Assistant Director-General for Access to Medicines and Health Products, in a press release. "This highlights the vital role of innovative diagnostic technologies in tackling one of the most lethal infectious diseases globally."
The latest annual report from the World Health Organization on tuberculosis indicates that 8.2 million individuals received a TB diagnosis in 2023. This marks the highest case count the organization has documented since it started tracking TB worldwide in 1995. Among these cases, around 400,000 were found to be resistant to multiple drugs.
