Most MDR-TB isolates in central China resistant to key MDR-TB drug
Chinese scientists have found that 62% of multidrug-resistant tuberculosis (MDR-TB) isolates they tested were also resistant to pyrazinamide (PZA), a key drug in treating MDR-TB, according to a study published yesterday in BMC Infectious Diseases.
The researchers analyzed 133 MDR-TB isolates collected from TB patients in Chongqing province in central China. They assessed for PZA resistance using a Bactec MGIT 960 system and then sequenced genes that conferred PZA resistance.
They found that 83 (62.4%) of the 133 isolated were PZA-resistant. In addition, resistance to streptomycin, ofloxacin, kanamycin, amikacin, and capromycin were more frequently observed among PZA-resistant isolates compared with PZA-susceptible isolates. And sequence analysis revealed that 73 (88.0%) of the MDR strains harbored a mutation located in the pncA gene.
PZA is typically subscribed in both first- and second-line treatments of MDR-TB.
Nov 6 BMC Infect Dis study
Madagascar's plague outbreak still slowing but tops 1,900 cases
Though the number of pneumonic plague infections and hospitalization are declining in Madagascar's outbreak, the World Health Organization (WHO) Regional Office for Africa said 146 more confirmed or suspected cases were reported since its last update on Oct 31, raising the total to 1,947.
Also, 16 more deaths were reported, putting the fatality number at 143. The outbreak's case-fatality rate held at 7%.
Plague is endemic and seasonal in Madagascar, with the bubonic form most common.The country, however, has been experiencing an unusual surge in the more deadly pneumonic plague, accounting for 74% of cases. Some of its biggest cities are among the hardest-hit areas. The pace of pneumonic cases has been declining since the middle of October, but the WHO has warned that new cases are likely through April, when Madagascar's plague season typically winds down.
Response efforts are still ramping up, with 346 health workers having been trained on infection prevention and control measures, and more medical staff have been hired for six treatment centers in Antananarivo, the country's capital, along with centers in Tamatave and Fenerive East.
The WHO estimates that $9.5 million is needed for the joint response, but so far only 26% of the total has been funded, and money received so far has already been spent on the response. Private-sector contributions such as broadcasting services, storage facilities, and personal protective equipment are increasing, the agency added. On Oct 31 the WHO and national authorities meet with Chinese experts to discuss collaboration and response support. As of Nov 6, the WHO and its partners have 151 experts deployed to Madagascar.
Nov 6 WHO situation update
Nigeria's monkeypox total climbs to 38 confirmed cases
Nigeria's number of lab confirmed monkeypox cases has jumped from 9 to 38 from eight states and the Federal Capital Territory (FCT), where the country's capital Abuja is located, though the number of cases reported over the last 2 weeks shows signs of slowing, the Nigeria Center for Disease Control (NCDC) said in its latest update.
Over the course of the outbreak, which began in late September, 116 suspected cases from 20 states and the FCT have been reported. Rapid response teams have been deployed to four states: Akwa Ibom, Bayelsa, Delta, and Enugu.
The epidemiologic investigation has found that twice as many males as females have been infected, and patients ages 21 to 40 years are the most affected age-group. States with the highest numbers of suspected and confirmed cases are in the southern part of Nigeria. So far no deaths have been reported.
As of late last week, 103 patient samples have been collected and sent for testing to the country's national laboratory in Lagos. Authorities are following 145 contacts, and 59 contacts have already completed their 21-day monitoring period.
Nov 3 NCDC monkeypox outbreak situation report
Takeda's dengue vaccine performed well in phase 2 trial
An 18-month interim phase 2 trial of Takeda's TAK-003 dengue vaccine proved to be safe and immunogenic in children ages 2 to 17. The results of the trial were published today in The Lancet Infectious Diseases and presented today at the American Society of Tropical Medicine and Hygiene's annual meeting.
The double-blind study looked at TAK-003's performance in 1,794 children living in the Dominican Republic, Panama, and the Philippines in both one-dose and two-dose schedules. Study subjects received either one primary dose of TAK-003, two primary doses of TAK-003 administered 3 months apart, one primary dose of TAK-003 followed by a booster dose 1 year later, or a placebo.
The results support a two-dose regimen administered 3 months apart. Participants who received the vaccine had a relative risk of symptomatic dengue of 0.29 (95% confidence interval, 0.13 to 0.72) compared with controls. Immunogenicity was achieved for all four dengue subtypes regardless of previous dengue virus exposure or infection.
"We are seeing an acceptable safety profile and sustained antibody responses out to 18 months in this trial. These data are an important step in the development of our dengue vaccine candidate," said Derek Wallace, MBBS, the global dengue program lead at Takeda, in a company press release. "The reduced incidence of dengue in children and adolescents receiving TAK-003 is encouraging."
An accompanying commentary in The Lancet Infectious Diseases said, "Overall, the interim results from this phase 2 trial are encouraging." TAK-003 is now being tested in a phase 3 trial.
Nov 7 Lancet Infect Dis study
Nov 7 Takeda press release
Nov 7 Lancet Infect Dis commentary
Long-term effects of West Nile virus seen on MRIs
Even patients who are symptom-free may have long-term brain damage from West Nile virus, according to a new study presented at the annual meeting of the American Society of Tropical Medicine and Hygiene (ASTMH) yesterday.
The study, conducted at the Baylor College of Medicine in Houston, tracked 262 people in the Houston area with West Nile virus from 2002 and 2012, and recruited 117 of those patients to be tested extensively for signs of neurological deficits. About half of the 117 patients, (57 or 49%) showed neurological and physical symptoms. Seven of those patients had no symptoms of neurological damage, but test results that showed neurological deterioration. Of those 57, 30 agreed to undergo magnetic resonance imaging (MRI), which showed damage or thinning in different parts of the cerebral cortex.
"The issues we are seeing on the MRIs are consistent with what would occur from an infection that caused a lot of inflammation in the brain," said Kristy Murray, DVM, PhD, of Baylor's National School of Tropical Medicine and the lead author of the study, according to an ASTMH news release. "Inflammation can lead to scarring as the brain starts to heal, and that scarring can cause damage."
Nov 7 ASTMH press release