French authorities have placed seven more departments covering major cities such as Lille, Strasbourg and Dijon on high alert as increases in Covid-19 infections accelerate, the government has said.
Of France's 101 mainland and overseas departments, 28 are now considered "red zones" where authorities will be able to impose exceptional measures to slow the number of new coronavirus cases.
The move comes as France reported a record of nearly 9,000 daily cases on Friday, and a further 8,550 cases in the past 24 hours, when the nationwide test positivity rate increased to 4.7%.
Paris and the Bouches-du-Rhone department encompassing the southeastern city of Lyon were the first to be placed on high alert by the government on 14 August after infection rates began to climb.
That prompted local officials to require face masks in all public spaces to slow the virus's spread, in hope of avoiding a spike in cases that could again overwhelm hospitals as autumn approaches.
The Sante Publique France health agency, which has warned of "exponential" caseload increases, said Saturday that 53 new outbreak clusters had been discovered in the previous 24 hours, bringing the total number under investigation to 484.
Twelve more Covid-19 deaths were reported, for an overall toll of 30,698 since the pandemic flared last March.
Concerns over infection risks have already prompted officials to close 22 schools after cases were detected just days after students returned from the summer break last week, and dozens of individual classes have also been suspended.
The French government said pre-school teachers as well as those with deaf students would soon be given transparent masks to facilitate comprehension at a crucial education stage for young children.
"More than 100,000 of these masks will be produced by the end of this month," the state secretary in charge of people with disabilities, Sophie Cluzel, told the Journal du Dimanche newspaper.
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Costa Rica researchers to trial treatment from horse antibodies
Researchers in Costa Rica are due to begin trials of an inexpensive coronavirus treatment based on antibodies taken from horses injected with the SARS-Cov-2, the virus that causes Covid-19, according to scientists.
Developed by University of Costa Rica's Clodomiro Picado Institute, the equine antibodies medication is to be tested on 26 patients from mid-September, Roman Macaya, president of the Social Security Fund that manages public health centers, told Reuters.
Costa Rican authorities hope to be able to begin applyin gthe treatment more widely in hospitals if the results from the phase 2 study are encouraging. There are 471 hospitalised coronavirus patients in Costa Rica.
"We are proud to know that this product will save lives until the vaccine reaches the population," said Alberto Alape, a project coordinator at ICP.
"We do it with our resources, without having to stand in line or compete against other countries, as can be seen with possible vaccines."
Similar efforts are also underway in Argentina and Brazil, while scientists in Belgium are using llamas.
Costa Rican researchers say their method for Covid-19 treatment is based on the experience of using horse antibodies to develop snake anti-venoms.
They imported the virus protein from China and the UK and injected it into six of the 110 horses that the IPC uses for testing.
Weeks later, when the animals developed enough antibodies, they extracted blood and used the antibodies from the plasma as raw material for the injectable serum.
If it works, the researchers say they want to share the inexpensive treatment with other Central American nations, which are mostly poorer than Costa Rica.
