H5N1

China: Investigation urged as deadly H7N9 strain of bird flu shows signs of drug resistance

Via the March 1 South China Morning Post: Investigation urged as deadly H7N9 strain of bird flu shows signs of drug resistance. Excerpt:

Experts said signs of resistance in a new strain of the deadly H7N9 bird flu virus against a drug used to treat people with the infection needs swift investigation to clarify how to handle the mutation. 

Two patients in Guangdong province with a new and more virulent strain of the virus have shown signs of failing to respond to the drug Tamiflu, the Nanfang Daily reported this week, citing Zhong Nanhsan, an expert in respiratory diseases. 

Virologists said the finding did not mean the drug was ineffective against bird flu, but a swift investigation was needed to assess how to handle the situation. 

There have been over 1,200 laboratory confirmed cases of human infection for bird flu in mainland China since the first was reported in 2013. As of Sunday, 94 people have died from the illness on the mainland this year.  

The drug resistance was found in two patients found to have the mutation of the virus, the report said. 

The new strain was identified by the China Centre for Disease Control earlier this month. 

Zhong was quoted a saying most patients were responding to Tamiflu treatment, suggesting the mutated strain of H7N9 was not the dominant virus, or “a considerable amount of viruses” did not mutate. 

He Jianfeng, chief expert in infectious diseases at the Guangdong Provincial Centre for Disease Control and Prevention, told the newspaper both patients with the new strain had taken Tamiflu before and it was not clear whether the drug resistance was caused by previous use of the treatment or the virus mutation.  

Professor Malik Peiris, a virologist at the University of Hong Kong who published a paper in the medical journal The Lancet four years ago saying H7N9 patients in Shanghai had previously shown antiviral resistance, said Tamiflu resistance occurred occasionally in bird flu patients treated with the drug before.

His further work showed these patients can be treated with alternative antiviral drugs.

Variation in Aedes aegypti mosquito competence for Zika virus transmission

Via Emerging Infectious Diseases: Ahead of Print -Variation in Aedes aegypti Mosquito Competence for Zika Virus Transmission. The abstract:

To test whether Zika virus has adapted for more efficient transmission by Aedes aegypti mosquitoes, leading to recent urban outbreaks, we fed mosquitoes from Brazil, the Dominican Republic, and the United States artificial blood meals containing 1 of 3 Zika virus strains (Senegal, Cambodia, Mexico) and monitored infection, dissemination, and virus in saliva. 

Contrary to our hypothesis, Cambodia and Mexico strains were less infectious than the Senegal strain. Only mosquitoes from the Dominican Republic transmitted the Cambodia and Mexico strains. However, blood meals from viremic mice were more infectious than artificial blood meals of comparable doses; the Cambodia strain was not transmitted by mosquitoes from Brazil after artificial blood meals, whereas 61% transmission occurred after a murine blood meal (saliva titers up to 4 log10 infectious units/collection). 

Although regional origins of vector populations and virus strain influence transmission efficiency, Ae. aegypti mosquitoes appear to be competent vectors of Zika virus in several regions of the Americas.

Liberia: Ebola survivor and frontline fighter dies after childbirth complications

Via The Guardian: Ebola survivor and frontline fighter dies after childbirth complications. Excerpt:

A woman named a Time magazine person of the year in 2014 for her frontline work fighting Ebola in west Africa has died from childbirth complications in Liberia. Hospital staff were reluctant to treat her because of the stigma that still surrounds the disease, according to her family.  

Salomé Karwah lost her parents, her brother, aunts, uncles, cousins and a niece in the Ebola outbreak that swept her home country in August 2014. She also contracted the disease, but survived, along with her sister, Josephine Manley, and her then-fiance, who was to become her husband, James Harris. 

Determined to help others, in October 2014, she wrote in the Guardian about her experiences as a survivor and her work as a mental health counsellor at an Ebola treatment centre run by Médecins San Frontières outside Monrovia, Liberia’s capital.  

Karwah died on the 21 February, four days after giving birth to her fourth child, Solomon, by caesarian section. Within hours of being discharged from hospital, she went into convulsions, according to her sister. She was rushed back to hospital but no one would touch her, as her foaming mouth and seizures panicked the staff.  

“They said she was an Ebola survivor,” Manley told Time magazine. “They didn’t want contact with her fluids. They all gave her distance. No one would give her an injection.” 

Karwah died the next day. Manley said she does not know what caused the convulsions, but believes that something could have gone wrong during her caesarian operation. She believes her sister may have had a chance of survival if she had been treated immediately. Instead, “she was stigmatised”, Manley said. 

“My heart is broken. Salomé loves her children, her James. The one-year-old, the newborn, they will grow up never remembering their mother’s face,” said Manley. 

Ella Watson-Stryker, who worked with Karwah in Liberia for MSF and was also among the Ebola fighters on the 2014 Time cover, said: “To survive Ebola and then die in the larger yet silent epidemic of health system failure … I have no words.”  

Vickie Hawkins, MSF’s executive director in the UK, described Karwah as a “brave figurehead” in the fight to end stigma for Ebola survivors. 

Hawkins said: “We are shocked and saddened to learn of the death of Salomé Karwah. Salomé first came to MSF as an Ebola patient and after bravely fighting a disease that killed her parents, she returned to provide mental health support to Ebola patients. She wanted to show people that survival was possible. 

“Our many staff who remember working with her speak of her strength and compassion, but also of her smile. She made a huge contribution to MSF’s work at the height of the outbreak in Monrovia.”

Branswell: Human cases of H7N9 bird flu are surging, officials say

Via STAT, Helen Branswell writes: Human cases of H7N9 bird flu are surging, officials say. Excerpt:

ATLANTA — Scientists and public health authorities are expressing alarm about an extraordinary surge in bird flu infections among humans. 

The H7N9 bird flu virus, which has sickened and killed several hundred people in China for the past four winters, had seemed over the past couple of years to be diminishing as a threat. 

But a resurgent wave of activity this winter has produced more than a third of all infections recorded since the first human case was hospitalized in February 2013. And with this large burst of cases, H7N9 has overtaken another bird flu, H5N1, which has been causing sporadic human infections at least a decade longer than H7N9.

Changes in the virus are also worrying, said Dr. Daniel Jernigan, director of the Centers for Disease Control and Prevention’s influenza branch. Jernigan noted Tom Price, the new health and human services secretary, has been briefed on the situation. 

“We’re concerned about the uncertainties here and the number of changes that are happening at this point. We are monitoring this closely,” Jernigan told STAT.    

To date, all of the infections have been contracted in China, although a few cases involved tourists from elsewhere who were infected there.  

Overall, 460 of the 1,258 H7N9 cases have been recorded in the latest wave of cases. About a third of people who have been diagnosed with H7N9 have died from their infections — though experts note undetected mild cases are probably occurring, which would lower that case fatality rate. 

“The situation is not particularly reassuring at the moment in the field,” said Professor Malik Peiris, head of the microbiology department at the University of Hong Kong. Peiris, a veteran bird flu researcher, called H7N9 “the most significant pandemic threat currently.” 

A CDC risk assessment concurs, placing H7N9 at the top of the list of pandemic threats from among a dozen bird and animal flu viruses.

Saudi Arabia: Three new MERS cases on February 27

Via the KSA MOH Command and Control Center on February 27: MOH: '3 New Confirmed Corona Cases Recorded'. The cases all involve Saudi men, two of them with direct camel contact, in Bisha, Hail, and Riyadh. Two are in critical condition and one is in stable condition. 

A 30-year-old Saudi man in Jeddah has recovered. No deaths are reported.

Singapore Zika update: One new case

The National Environment Agency has published its Zika Cases & Clusters updates for February 27 and 28. One case was reported on the 27th, none on the 28th. This is the first Zika case in Singapore in about two weeks.

Taiwanese man dies of H7N9 avian flu

Via Focus Taiwan, a CNA report: Taiwanese man dies of H7N9 avian flu.

A 69-year-old man who contracted the H7N9 avian flu virus in China last month has died, becoming the first Taiwanese victim of that virus strain, the Centers for Disease Control (CDC) said Tuesday. 

The businessman died late Monday, said Lo Yi-chun (羅一鈞), deputy director-general of the CDC. The patient had been in hospital in Kaohsiung for 27 days after falling ill in China and returning to Taiwan on Jan. 25 to seek medical help. 

Since 2013, it was the fifth confirmed human infection in Taiwan of H7N9, a subtype of the avian influenza A virus, and the man was the second patient to have died from the disease.  

The other fatal case, which occurred in Dec. 2013, involved an 86-year-old Chinese tourist who died from the disease while visiting in Taiwan.

Asymptomatic infection and unrecognised Ebola virus disease in Ebola-affected households in Sierra Leone

Via The Lancet Infectious Diseases: Asymptomatic infection and unrecognised Ebola virus disease in Ebola-affected households in Sierra Leone: a cross-sectional study using a new non-invasive assay for antibodies to Ebola virus. The summary:

Background 

The frequency of asymptomatic infection with Ebola virus is unclear: previous estimates vary and there is no standard test. Asymptomatic infection with Ebola virus could contribute to population immunity, reducing spread. If people with asymptomatic infection are infectious it could explain re-emergences of Ebola virus disease (EVD) without known contact. 

Methods 

We validated a new oral fluid anti-glycoprotein IgG capture assay among survivors from Kerry Town Ebola Treatment Centre and controls from communities unaffected by EVD in Sierra Leone. We then assessed the seroprevalence of antibodies to Ebola virus in a cross-sectional study of household contacts of the survivors. All household members were interviewed. Two reactive tests were required for a positive result, with a third test to resolve any discrepancies.  

Findings 

The assay had a specificity of 100% (95% CI 98·9–100; 339 of 339 controls tested negative) and sensitivity of 95·9% (89·8–98·9; 93 of 97 PCR-confirmed survivors tested positive). Of household contacts not diagnosed with EVD, 47·6% (229 of 481) had high level exposure (direct contact with a corpse, body fluids, or a case with diarrhoea, vomiting, or bleeding). Among the contacts, 12·0% (95% CI 6·1–20·4; 11 of 92) with symptoms at the time other household members had EVD, and 2·6% (1·2–4·7; 10 of 388) with no symptoms tested positive. Among asymptomatic contacts, seropositivity was weakly correlated with exposure level. 

Interpretation 

This new highly specific and sensitive assay showed asymptomatic infection with Ebola virus was uncommon despite high exposure. The low prevalence suggests asymptomatic infection contributes little to herd immunity in Ebola, and even if infectious, would account for few transmissions.

See also this comment on the report.

WHO: Human infection with avian influenza A(H7N9) virus – China

WHO has published Human infection with avian influenza A(H7N9) virus – China. Excerpt:

On 18 February 2017, the National Health and Family Planning Commission of China (NHFPC) reported to WHO the results of genetic sequencing on virus isolates from two previously reported cases of human infection with avian influenza A(H7N9) virus from Guangdong province. Changes at the cleavage site of the HA gene suggestive of being highly pathogenic to poultry was confirmed by the Chinese National Influenza Centre of the Chinese Centre for Disease Control and Prevention (China CDC).  

Details of the cases 

The two cases were reported through International Health Regulations (IHR) notification on 19 January 2017.  

• A 43-year-old female with symptom onset on 29 December 2016. The case recovered. She had poultry exposure but also cared for her sister who was hospitalized with avian influenza A(H7N9). This was reported as a family cluster. 

• A 57-year-old male with symptom onset on 5 January 2017. The case is still hospitalized and in critical condition as of 22 February 2017. He was reported to have had poultry exposure. 

Investigation revealed exposure to sick and dead poultry. None of the 105 close contacts of these two cases developed symptoms during the two weeks of medical observation. To date, there is no evidence of changes in pathogenicity to and transmissibility among humans. 

Public health response 

Considering the new developments in H7N9 genetic sequence, the Chinese government is implementing additional measures in Guangdong province on top of current existing measures:  

• Closure of markets for cleaning. 

• Emergency monitoring of poultry markets and flocks. 

• Culling of flocks if the strain is confirmed in them. 

WHO risk assessment 

This is the first report of avian influenza A(H7N9) virus, since its emergence in 2013, having genetic sequences that are suggestive of evolving from a low pathogenic into a highly pathogenic avian virus. Similar changes at the cleavage site of the HA gene were also found in genetic sequence data uploaded in Global Initiative on Sharing Avian Influenza Data (GISAID) of a virus from a recent human case reported by Taiwan, China earlier to WHO on 4 February 2017 with travel history to Guangdong. 

In addition the Ministry of Agriculture China reported to World Organisation for Animal Health (OIE) on 21 February 2017 that genetic sequences of virus samples from live poultry markets in Guangdong also showed changes consistent with highly pathogenic avian influenza viruses. So far the above genetic changes have been found in viruses from human, poultry and environmental samples from Guangdong or with travel history to Guangdong province.  

In addition the genetic sequences from the two human cases from Guangdong and the case reported by Taiwan, China showed amino acid substitutions associated with neuraminidase inhibitor antiviral drug resistance. It was reported that the three patients received antiviral treatment before samples were taken. 

So far there is no evidence of change of epidemiological patterns of avian influenza A(H7N9) infection in humans. There is no evidence that a change in the virus from low pathogenic to high pathogenic avian influenza virus has an impact on the pathogenicity or transmissibility in humans. 

Overall the likelihood of further community level spread remains low.

For some useful commentary on this report, see Mike Coston's post on Avian Flu Diary.

Chile floods leave millions of people without drinking water in Santiago

Via The Guardian: Chile floods leave millions of people without drinking water in Santiago. Excerpt:

Millions of people are without water after heavy rains struck Chile over the weekend during the country’s usually dry summer months, leaving three people dead and at least 19 missing.  

The rains, which caused rivers to overflow their banks in mountain valleys near Chile’s capital, Santiago, had isolated 373 people, the Onemi emergency service said late on Sunday.

The drinking-water supply for over a million households in Santiago had been affected, and Aguas Andinas, the company that provides water to the capital, said rains were making repairs difficult. Agence France-Presse estimated four million people were affected. 

“Emergency teams are working on the ground to connect with isolated persons and re-establish the water supply wherever possible,” Chilean president Michelle Bachelet wrote on Twitter.