Dengue case recorded in Florida Keys, more cases in French Caribbean

Florida Health officials confirmed a case of locally acquired dengue in the Florida Keys, according to the Associated Press (AP), and said the patient is doing well. The Keys saw outbreaks of the mosquito-borne disease in 2009 and 2010.

Also today, the World Health Organization (WHO) reported a sharp uptick of dengue cases in French Caribbean regions, including French Guiana, Guadeloupe, Martinique, and Saint-Martin.

"In January 2020, health authorities in the region declared a dengue epidemic in Guadeloupe and Saint-Martin and indicated that Martinique is also at-risk of an epidemic," the WHO said.

In French Guinea, 487 confirmed dengue case have been recorded since January 2019, Guadeloupe has had 5,840 cases since October 2019, Martinique has logged 2,470 suspected and 575 confirmed cases since July 2019, and Saint-Martin has had 530 suspected cases, including one severe and fatal case, since Jan 12, 2020. One hundred suspected cases have also been documented in Saint-Barthelemy.

A shift to the dengue 2 serotype in circulating strains has likely spurred the epidemics, the WHO said: "A shift in the predominant DENV serotype in these territories may result in more severe secondary dengue virus infections and may require comprehensive risk communications."
Mar 10 AP story
Mar 10 WHO


WHO update details H9N2 avian flu cases, swine-origin H1N1v infection

In its latest monthly zoonotic flu update, the WHO noted two human H9N2 avian flu infections and one variant H1N1 (H1N1v) swine-origin flu illness.

One of the H9N2 cases involves a 7-year-old Hong Kong boy whose H9 illness was first reported by Hong Kong health officials on Feb 7. The boy got sick on Feb 4 and was hospitalized the next day. He had visited relatives in Guangdong province on the mainland. Though the relative kept backyard poultry, the boy did not have direct exposure to the birds. No other cases were detected.

The second H9N2 case involves a child from Senegal, apparently a first for that country. The illness was detected in February 2019 in Ziguinchor region when the patient was seen at an outpatient clinic. He or she was not hospitalized and has since recovered. Backyard poultry are the likely exposure source. H9N2 illnesses are usually mild, and no deaths have been reported. The WHO said H9N2 is enzootic in Asian poultry and has increasingly been reported in African poultry.

Meanwhile, the H1N1v case was detected in a 38-year-old man from Hebei province, China, who was sick in the middle of November 2019. He had mild illness, which was found during routine flulike illness surveillance. No information on his contacts or exposure source was available. The WHO said most human cases of swine influenza involve contact with infected pigs or their environments. Illnesses in humans are typically mild.
Feb 28 WHO monthly zoonotic flu risk assessment


Study shows that the broad-spectrum flu vaccine FLU-v triggers immunity

Results of a phase 2b trial in the Netherlands show that a universal, standalone flu vaccine is safe and induces a strong immune response, moving it closer to phase 3 clinical trials to determine its effectiveness, according to a study today in the Annals of Internal Medicine.

The randomized, double-blind trial demonstrated that FLU-v, a vaccine designed to prevent infection with influenza A and B, produced antibodies to the strains tested and cell-mediated immunity. The study authors said the vaccine merits phase 3 development, meaning it will join three other broad-spectrum (or universal) vaccines in that stage of development: BiondVax's M-001, Medicago's QVLP, and Novavax's NanoFlu. FLU-v is made by hVIVIO of London, England.

The investigators studied the vaccine's effects in 175 healthy adults, 18 to 60 years old, at a single center. The subjects received an under-the-skin injection of either one dose of 0.5-milliliters antigen and 500 micrograms of adjuvant, two doses of nonadjuvanted FLU-v, or adjuvanted or nonadjuvanted placebo in a 2:2:1:1 ratio. An adjuvant is an agent added to a vaccine to boost the strength and length of the body's immune response.

Using flow cytometry and enzyme-linked immunosorbent assay, the researchers evaluated vaccine-specific cellular responses on the day of infection and 42 and 180 days afterward. The study was not powered to measure vaccine effectiveness against the flu.

The researchers also determined that most adverse events associated with immunization were mild to moderate reactions at the injection site.

Although the best way to prevent the flu is annual vaccination, seasonal vaccines offer little cross-protection, which can reduce their effectiveness. Universal vaccines aim to protect against not only multiple strains but novel ones, as in the case of influenza pandemics.
Mar 10 Ann Intern Med

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