COVID-19: Brazil under third wave of the pandemic

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Brazil on Saturday became the second country after the United States to surpass 500,000 COVID-19 deaths as the South American giant grapples with a third wave of the pandemic.

“500,000 lives lost due to the pandemic that affects our Brazil and the world,” Health Minister Marcelo Queiroga tweeted.

The Health Ministry reported 500,800 deaths, including 2,301 in the last 24 hours, a toll that many experts say underestimate the real toll from the health crisis.

This week the average number of daily deaths surpassed 2,000 for the first time since May 10.

“The third wave is arriving, there’s already in a change in the case and death curves,” Ethel Maciel, an epidemiologist from Espirito Santo University, told AFP.

“Our vaccination (program), which could make a difference, is slow and there are no signs of restrictive measures, quite the contrary.”

In large cities, life seems almost back to normal with restaurants, bars and shops open and many people in the streets not wearing face masks.

And yet the situation is critical in 19 of Brazil’s 27 states with more than 80 percent occupancy of intensive care beds—in nine of those states it’s over 90 percent.

‘Marathon runner’

The “second wave,” from January to April this year, was particularly deadly.

The number of deaths increased exponentially with the arrival of the Gamma virus variant that originated in Manaus, in the north of Brazil.

It gradually began to fall in May thanks in part to the closure of businesses when the pandemic was at its worst.

But many epidemiologists believe lockdown restrictions were lifted too soon at a time when daily deaths were still up around the 2,000 mark.

Contrary to what has been seen in Europe, there’s been no real trough between the different waves in Brazil.

“I don’t know if it’s a third wave … it seems we never got out of the first one,” said Alexandre da Silva, a specialist in public health at the University of Sao Paulo.

“It seems the pandemic has now turned into a marathon runner who is pacing his race. It’s not a sprinter who does his sprint but then loses power.”

Brazil has recently received several batches of vaccines, including from US pharmaceutical giant Pfizer, but the country has only managed to fully vaccinate 11 percent of the population, with 29 percent receiving one dose.

The vaccination drive began late in mid-January using the AstraZeneca and Coronavac jabs.

Far-right President Jair Bolsonaro, who previously hit out at vaccines, has promised to immunize the entire population by the end of the year—something specialists consider unlikely.

Bolsonaro has been criticized for downplaying the pandemic from the outset, opposing lockdown measures and plugging unproven medical treatments for COVID, and on Saturday thousands of Brazilians again took to the streets in protest against him.

In rallies in Rio de Janeiro, Brasilia and elsewhere, people carried banners with slogans like “Bolsonaro must go” or simply “500,000.”

“His position on COVID and his denialism are absurd. He has abandoned reality and common sense. There is no explaining this, it is surreal,” said Robert Almeida, a 50-year-old photographer marching in Rio.

“500,000 deaths from a disease for which there is now a vaccine, in a country that has been a world leader in vaccination. There is a word for that: genocide,” leftist former president Luiz Inacio Lula da Silva tweeted. “Solidarity with the people of Brazil.”

Copa COVID

It was all the more surprising, then, that Brazil agreed at the 11th hour to host the Copa America football tournament, seeing global stars such as Argentina’s Lionel Messi, Luis Suarez of Uruguay and the hosts’ own Neymar arrive from their European clubs.

The matches are being played behind closed doors but Bolsonaro has come under fire for giving his blessing to host the tournament in the midst of a pandemic when both Argentina and Colombia had to pull out.

Many Brazilians have voiced their opposition to the tournament.

Beyond the football tournament, Maciel says the government’s pandemic management is responsible for thousands of extra deaths.

“If we had acted in a different and coordinated way, giving concrete information to the people on public health measures… none of this would have happened,” she said.

She accused the government of “confusing the people” by advising against health measures backed by science, such as social distancing and the use of face masks.

Bolsonaro shows no signs of changing tack, though, and last week announced he would ask the health minister to lift the requirement to wear masks outdoors.

He has already been hit with several fines by local authorities for holding rallies without wearing a mask.

And Bolsonaro is also under investigation by the Senate over his chaotic pandemic management.


Global overview

Data as of 6 June 2021

Global case and death incidences continued to decrease with over 3 million new weekly cases and over 73 000 new deaths, a 15% and an 8% decrease respectively, compared to the previous week (Figure 1). The European and South-East Asia Regions reported marked declines in the number of new cases in the past week, whereas the African Region reported an increase compared to the previous week (Table 1). The Region of the Americas as well as the Eastern Mediterranean and the Western Pacific Regions reported similar numbers compared to the previous

week. The number of new deaths reported in the past week decreased in the European and South-East Asia Regions and increased in the Western Pacific Region. Death incidences remained stable in the Region of the Americas as well as the Eastern Mediterranean and African Regions. Despite the downward trend in global case and death incidences for a sixth and fifth consecutive week respectively, many countries across all six regions have reported rises in the number of cases and deaths.

The highest numbers of new cases were reported from India (914 539 new cases; 33% decrease), Brazil (449 478 new cases; 7% increase), Argentina (212 975 new cases; 3% decrease), Colombia (175 479 new cases; 17% increase), and the United States of America (99 103 new cases; 35% decrease).

Table 1. Newly reported and cumulative COVID-19 cases and deaths, by WHO Region, as of 6 June 2021**

  WHO RegionNew cases in last 7 days (%)Change in new cases in last 7 days *Cumulative cases (%)New deaths in last 7 days (%)Change in new deaths in last 7 days *Cumulative deaths (%)
Americas1 191 047 (39%)-1%68 370 018 (40%)34 392 (47%)4%1 794 865 (48%)
Europe368 874 (12%)-17%54 629 665 (32%)8 890 (12%)-21%1 157 890 (31%)
South-East Asia1 049 694 (35%)-31%32 654 915 (19%)23 369 (32%)-21%425 123 (11%)
Eastern Mediterranean202 208 (7%)-5%10 278 904 (6%)3 503 (5%)-1%205 145 (6%)
Africa65 943 (2%)25%3 563 825 (2%)1 167 (2%)2%88 274 (2%)
Western Pacific138 239 (5%)-1%3 139 006 (2%)2 486 (3%)19%47 634 (1%)
Global3 016 005 (100%)-15%172 637 097 (100%)73 807 (100%)-8%3 718 944 (100%)
*Percent change in the number of newly confirmed cases/deaths in past seven days, compared to seven days prior
**See Annex 3: Data, table and figure notes

Special Focus: Update on SARS-CoV-2 Variants of Interest (VOIs) and Variants of Concern (VOCs)

WHO, in collaboration with national authorities, institutions and researchers, routinely assesses if variants of SARS-CoV-2 result in changes in transmissibility, clinical presentation and severity, or if they result in changes in the implementation of public health and social measures (PHSM) by national health authorities. Systems have been established to detect “signals” of potential Variants of Concern (VOCs) or Variants of Interest (VOIs) and assess these based on the risk posed to global public health. Table 2 lists currently designated global VOIs and VOCs. National authorities may choose to designate other variants of local

interest/concern. Here we provide an update on emerging evidence surrounding phenotypic characteristics and the geographical distribution of designated VOCs.

On 31 May 2021, WHO announced new easy-to-say/easy-to-remember VOI and VOC labels to facilitate public communication about SARS-CoV-2 variants and the 1 June 2021 edition of the WEU outlined the changes in labelling of the VOCs and VOIs, as well as updates to the classifications of variants B.1.617.1, B.1.617.3 and B.1.616.

Table 2: SARS-CoV-2 Variants of Concern (VOCs) and Variants of Interest (VOIs), as of 8 June 2021

Table 3: Summary of phenotypic impacts* of Variants of Concern (VOCs)

Phenotypic characteristics

Available evidence on phenotypic impacts of VOCs and vaccine performance against VOCs are summarised in Tables 3, as well as in previous editions of the WEU.

Recent studies of the Delta variant in the United Kingdom of Great Britain and Northern Ireland suggest a possible increased risk of severe disease, and support previous observations of increased transmissibility.5 An analysis comparing Delta and Alpha variant confirmed cases in the United Kingdom from 29 March to 20 May 2021 showed the Delta variant was associated with a possible increased risk of hospitalization (hazard ratio 2.61, 95%CI 1.56-4.36), and an increased risk of emergency care attendance or hospitalization (hazard ratio 1.67, 1.25-2.23) within 14 days of specimen collection, as compared to the Alpha variant.

A second analysis based on cases reported in the United Kingdom from 29 March to 11 May 2021 (variant data as of 25 May 2021) found that the secondary attack rate was higher among contacts of Delta cases compared to contacts of Alpha cases (2.6% vs. 1.6% among contacts of cases that have travelled; 8.2% vs. 12.4% among contacts of cases that have not travelled). Further analyses are required to better understand and confirm these findings.

VOC impacts on vaccines

Since the update on VOC impacts on vaccines on 25 May, two studies have provided further evidence of the effectiveness of Pfizer BioNTech-Comirnaty vaccine against VOCs. A study from Canada found two doses of the vaccine to be 90% (95% CI: 85-94%) and 88% (95% CI: 61-96%) effective against symptomatic disease ≥7 days post second dose caused by variants Alpha and Beta/Gamma, respectively, among adults 16 years and older.

Vaccine effectiveness (VE) against hospitalization/death ≥0 days post second dose was 94% (95%CI: 55-99%) for Alpha and 100% (95% CI not available) for Beta/Gamma. VE of a single dose of Pfizer BioNTech- Comirnaty against symptomatic disease (≥14 days after immunization) was 61% (95% CI: 59-66%), 43% (95% CI: 22-59%), and 61% (95% CI: 53-67%) for Alpha, Beta, and for Gamma, respectively, underscoring the importance of two doses of vaccine in preventing symptomatic disease.

Samples bearing the 501Y mutation without the E484K mutation were assumed to be Alpha while samples bearing the 501Y mutation with the E484K mutation were assumed to be either Beta or Gamma.27 Samples bearing the 501Y mutation without the E484K mutation were assumed to be Alpha while samples bearing the 501Y mutation with the E484K mutation were assumed to be either Beta or Gamma.27 Samples bearing the 501Y mutation without the E484K mutation were assumed to be Alpha while samples bearing the 501Y mutation with the E484K mutation were assumed to be either Beta or Gamma.27

A previously highlighted study from Qatar found two doses of Pfizer BioNTech-Comirnaty to be highly effective against Alpha infection (VE 89.5%) and severe disease (VE 100%); the vaccine was also highly effective against severe disease caused by Beta with a VE of 100% but somewhat reduced against infection (VE 75%) due to this variant.24

A follow-up analysis (not yet peer-reviewed) to this study evaluated the effectiveness of one dose of Pfizer BioNTech-Comirnaty against infection and severe disease caused by Alpha and Beta variants. At 1-7 days and 8-14 days post vaccination, low to no effectiveness against infection and severe disease was observed for disease events caused by these variants.

At 15-21 days post vaccination, VE estimates against infection and severe disease due to Alpha were 65.5% (95% CI: 58.2-71.5%) and 72.0% (95% CI: 32.0-90.0%), respectively. VE estimates against infection and severe disease due to Beta were 46.5% (95% CI: 38.7-53.3%) and 56.5% (95% CI: 0.0-82.8%), respectively.

These findings underscore the importance of two doses in preventing infection and severe disease caused by Alpha and Beta. Of note, infections that were not due to Alpha were assumed to be caused by Beta variant as national surveillance did not detect any other strains circulating during much of the study period.80

Two recent studies provide evidence of reduced neutralization capacity of COVID-19 vaccines against variant Delta. One study found a 5.8-fold reduction in neutralization against Delta compared to a reference strain in 159 samples from individuals who received two doses of Pfizer BioNTech-Comirnaty [median time after second dose: 28 days (IQR: 21-37)]; 2.6- and 4.9-fold reductions were observed against Alpha and Beta variants, respectively, relative to the reference strain.60 Findings from a second study (not yet peer-reviewed)

show a 3-fold reduction in neutralization capacity against Delta relative to Alpha among sera collected from 16 individuals five weeks after receipt of second dose of Pfizer BioNTech-Comirnaty; a 16-fold reduction was observed against Beta relative to Alpha. Most samples (81-100%) were able to neutralize Alpha, Beta and Delta five weeks after receipt of the second dose; findings remained consistent at 13 weeks after second dose with the exception of the Beta strain whereby only 46% of samples were able to neutralize the variant. Authors also found that a single dose of AstraZeneca-Vaxzevria, while able to neutralize Alpha, was less effective at neutralizing Beta or Delta.78

Two recent studies (not yet peer reviewed) provide evidence of the impact of heterologous vaccination on neutralization capacity against variants. In both studies, individuals received AstraZeneca-Vaxzevria as a first dose followed by a Pfizer BioNTech-Comirnaty booster. The first of these studies compared 26 individuals receiving heterologous vaccination to 14 individuals receiving two doses of Pfizer BioNTech-Comirnaty.

Overall, authors report a strong neutralization response in heterologous vaccinated individuals against Alpha, Beta and B.1.617 (lineage not specified) exceeding neutralization titers of the homologous vaccination group, though the difference for B.1.617 was not statistically significant. Results also show that, among the heterologous group, a two-fold reduction in neutralization capacity was observed against Beta relative to Alpha, though neutralization was still achieved; no such reduction was observed for B.1.617.

In addition, CD4+ or CD8+ T cells were detected two weeks after heterologous vaccination, with results similar to those from studies evaluating a single dose of AstraZeneca-Vaxzevria and homologous Pfizer BioNTech-Comirnaty vaccination.81 The second study compared the AstraZeneca-Vaxzevria/Pfizer BioNTech-Comirnaty heterologous group to a homologous group receiving two doses of AstraZeneca-Vaxzevria and found higher neutralization against Alpha, Beta and Gamma in the heterologous group. Increased CD4+ and CD8+ T cell reactivity was also observed in the heterologous group.82 Together, these studies provide evidence that a heterologous vaccination regimen is at least as protective as homologous vaccinations.

Geographic distribution

As surveillance activities to detect SARS-CoV-2 variants are strengthened at local and national levels, including by strategic genomic sequencing, the number of countries/areas/territories (hereafter countries) reporting VOCs has continued to increase (Figure 3, Annex 2). This distribution should be interpreted with due consideration of surveillance limitations, including differences in sequencing capacities and sampling strategies between countries

Public health authorities are encouraged to continue to strengthen surveillance and sequencing capacities and apply a systematic approach to provide a representative indication of the extent of transmission of SARS- CoV-2 variants based on the local context, and in the investigation of unusual epidemiological events.

Environmental surveillance has the potential to support other early warning surveillance systems for monitoring the spread of SARS-CoV-2 infections, including variants. A recent study in the United Kingdom demonstrated the ability to detect co-circulating SARS-CoV-2 variants and identify changes in viral RNA sequences in wastewater.83

In Spain, weekly wastewater estimates of the proportion of variant Alpha in 32 different locations reflected the trends in reported sequenced clinical cases in most regions. Moreover, wastewater surveillance allowed the identification of variant Alpha circulation in new areas within Spain before detection by the public health authorities using clinical specimens.84

WHO recommendations

Virus evolution is expected, and the more SARS-CoV-2 circulates, the more opportunities it has to evolve. Reducing transmission through established and proven disease control methods such as those outlined in the COVID-19 Strategic Preparedness and Response Plan, as well as avoiding introductions into animal populations, are crucial aspects of the global strategy to reduce the occurrence of mutations that have negative public health implications. PHSM remain critical to curb the spread of SARS-CoV-2 and its variants. Evidence from multiple countries with extensive transmission of VOCs has indicated that PHSM, including infection prevention and control (IPC) measures in health facilities, have been effective in reducing COVID-19 case incidence, which has led to a reduction in hospitalizations and deaths among COVID-19 patients.

National and local authorities are encouraged to continue strengthening existing PHSM, IPC and disease control activities. Authorities are also encouraged to strengthen surveillance and sequencing capacities and apply a systematic approach to provide a representative indication of the extent of transmission of SARS-CoV-2 variants based on the local context, and to detect unusual events.

reference link: https://reliefweb.int/sites/reliefweb.int/files/resources/20210608_Weekly_Epi_Update_43.pdf

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