Pfizer Shot: Hospitalization Protection Or Not?

The Pfizer-BioNTech COVID-19 vaccine has been widely administered across the globe and has been shown to be effective in preventing severe illness and hospitalization, especially for older adults. While initial studies indicated high protection against the virus, the emergence of new variants, such as the Delta strain, has raised questions about the vaccine's effectiveness against infection and transmission. However, even with the Delta variant, the Pfizer vaccine has been found to provide high levels of protection against hospitalization, ranging from 60% to 92% in various studies. The vaccine's effectiveness in preventing hospitalization may vary depending on age, the number of doses received, and the time elapsed since vaccination.

Pfizer vaccine 91% effective in preventing hospitalization caused by the Delta variant

The Pfizer-BioNTech COVID-19 vaccine has been found to be effective in preventing hospitalizations, including those caused by the Delta variant. According to a report from Israel's health ministry, the vaccine provided 88% protection against hospitalization and 91% against severe illness for an unspecified number of people studied between June 20 and July 17, 2021. This data is significant as Israel was one of the first countries to gain early access to COVID-19 vaccines and has had a high vaccination rate, with about 60% of its population receiving at least one dose of the Pfizer vaccine.

While the Pfizer vaccine has shown strong effectiveness in preventing hospitalizations, its ability to prevent infection and symptomatic illness has been more limited, especially with the emergence of the Delta variant. The spread of the Delta variant in Israel coincided with a decrease in the vaccine's effectiveness in preventing infections and symptomatic illnesses, dropping to 64% since June 6, 2021, according to the Ministry of Health. This decline in effectiveness against the Delta variant has also been observed in other countries, with studies showing that two doses of the Pfizer vaccine offer 39% to 88% protection against symptomatic disease caused by the Delta variant.

It is important to note that the effectiveness of the Pfizer vaccine in preventing hospitalizations and severe illnesses caused by COVID-19, including the Delta variant, has been consistently high. This indicates that the vaccine provides a strong shield against the most severe outcomes of the disease. However, the vaccine's ability to prevent transmission and infection, especially from new variants like Delta, has been less effective. This has led to a rise in breakthrough infections, where fully vaccinated individuals can still get infected and spread the virus, even though they are protected from severe illness and hospitalization.

While the Pfizer vaccine has shown promising results in preventing hospitalizations, some studies have raised concerns about potential adverse events associated with the vaccine. An analysis of Pfizer and Moderna COVID-19 vaccine trials found an increased risk of serious adverse events, including inpatient hospitalization, for a small number of vaccinated individuals. However, it is important to note that this study has not yet been peer-reviewed, and the overall benefits of the vaccine in preventing severe illness and reducing hospitalizations outweigh these rare adverse events.

In conclusion, the Pfizer vaccine has been highly effective in preventing hospitalizations caused by the Delta variant, providing strong protection against the most severe outcomes of COVID-19. While its ability to prevent infections, especially with new variants, has shown some decline, the vaccine continues to play a crucial role in reducing the risk of hospitalization and severe disease. As more data becomes available and new variants emerge, ongoing research and analysis are essential to monitor the vaccine's effectiveness and make informed decisions regarding public health measures.

Pfizer vaccine 60-70% effective in preventing symptomatic COVID-19 in people 70+

The Pfizer-BioNTech COVID-19 vaccine has been found to be largely effective in preventing hospitalisation and severe cases of the disease. However, it is less effective against the Delta variant of the coronavirus. While the vaccine was 94.3% effective in preventing coronavirus infection when the Delta strain was less prevalent, it was only 64% effective during the month when the variant became more widespread.

A study from Hebrew University and Hadassah University Medical Center found that the Pfizer vaccine is 60-80% effective against infection from the Delta strain. Furthermore, according to Israeli Health Ministry figures, the vaccine blocks the majority of serious Delta cases.

In people aged 70 and above, the Pfizer vaccine has been found to be 60-70% effective in preventing symptomatic COVID-19. A study by Public Health England (PHE) found that one dose of the Pfizer vaccine was 57% to 61% effective in preventing symptomatic COVID-19 after four weeks. Another study from Israel found that the Pfizer vaccine reduced the risk of hospitalisation by 43% and the risk of death by 51% in this age group.

While the Pfizer vaccine has been shown to be effective in preventing severe disease and hospitalisation, it is important to note that vaccinated individuals can still get infected and spread the virus. Therefore, even after vaccination, it is crucial to continue following preventive measures such as good hand hygiene and staying at home when sick.

Pfizer vaccine 43% effective in preventing hospital admission for over-80s

A single dose of the Pfizer vaccine is highly effective in preventing hospital admissions in the over-80s. A Bristol study found that 14 days after one dose of the Pfizer vaccine, it was 79.3% effective at preventing people in that age group from developing symptomatic illness severe enough to be admitted. The study's results were confirmed by a Public Health England (PHE) report, which found that a single dose of the Pfizer vaccine was around 80% effective at preventing hospital admissions in over-80s three to four weeks after the first dose.

The PHE study also found that a single dose of the Pfizer vaccine led to an 85% reduction in deaths from Covid-19 in people aged 70 and over. The researchers in Bristol also found that the Oxford-AstraZeneca coronavirus vaccine was highly effective in preventing hospital admissions in the over-80s, with an effectiveness of 80.4%.

However, it is important to note that the effectiveness of the Pfizer vaccine in preventing hospitalization may vary depending on the variant of the coronavirus. For example, the vaccine has been found to be 64% effective in preventing coronavirus infection with the Delta variant, compared to 94.3% effectiveness when the strain was less prevalent.

While the Pfizer vaccine has been shown to be highly effective in preventing hospitalizations in the over-80s, there have been conflicting findings regarding its effectiveness in children. There are currently no scientific studies demonstrating that the Pfizer vaccine reduces the risk of hospitalization and death in children. An analysis of Pfizer vaccine trials found that the mRNA shots are more likely to result in hospitalization than provide protection from severe adverse events.

Overall, while the Pfizer vaccine has been shown to be effective in preventing hospitalizations in the over-80s, further research and data are needed to fully understand its effectiveness across different age groups and variants of the coronavirus.

Pfizer vaccine less effective in preventing the spread of the Delta variant

The Pfizer-BioNTech COVID vaccine is less effective at preventing the spread of the Delta variant of the coronavirus. Data from Israel's Health Ministry shows that the vaccine is significantly less effective against preventing infection and symptomatic illness with the Delta variant than with previous strains. The vaccine's effectiveness in preventing symptomatic COVID-19 has dropped to 64%, compared to 94.3% in May when the Delta variant was less prevalent.

The drop in efficacy is likely due to the Delta variant's increased resistance to vaccines and high transmissibility. The Delta variant is believed to be twice as contagious as the original strain of COVID-19 and is responsible for a significant number of new cases in Israel and other countries. This has led to a contentious debate among experts, officials, and pharmaceutical companies about the potential use of booster shots to top up waning immunity.

While the Pfizer vaccine may be less effective against the Delta variant, it still provides good protection against severe disease and hospitalizations. According to the Israeli government, the vaccine is 93% effective in preventing severe disease and hospitalizations, which is only slightly lower than against other variants. Public health officials stress that the current shots offer good protection against the Delta variant, with a study by Public Health England finding that the Pfizer vaccine is 96% effective against hospitalizations from the Delta variant after two doses.

It is important to note that the effectiveness of the vaccine against death has allowed countries like England to relax restrictions, despite the rapid increase in cases. However, the Israeli government has reinstated an indoors mask mandate after a spike in cases caused by the Delta variant, highlighting the ongoing need for caution and the consideration of various preventive measures.

Regarding the question of whether one shot of Pfizer prevents hospitalization, there is conflicting evidence. Some sources indicate that the Pfizer vaccine is highly effective in preventing hospitalization, even against the Delta variant. However, other sources suggest that there is a lack of scientific studies demonstrating that the COVID-19 vaccines, including Pfizer, reduce the risk of hospitalization, especially in children. It is important to consider the specific context, variant prevalence, and evolving nature of the pandemic when interpreting these findings.

Pfizer vaccine safe for children, but no studies on reducing hospitalization risk

While the Pfizer-BioNTech COVID-19 vaccine is considered safe for children, there is a lack of scientific studies demonstrating its effectiveness in reducing the risk of hospitalization and death in this age group. This has led to some controversy and differing opinions among health authorities and researchers.

The U.S. Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC) have played a significant role in the approval and recommendation of COVID-19 vaccines, including those for children. However, in May 2025, the U.S. government announced that it would no longer recommend routine COVID-19 vaccinations for healthy children and pregnant women. This decision was made despite President Biden's earlier push for parents to vaccinate their young children, claiming that the shots are "safe and effective."

The CDC's website states that studies with hundreds of thousands of participants worldwide show that COVID-19 vaccination during pregnancy is safe and beneficial to both mother and child. However, the CDC has also acknowledged that there is no evidence to support a repeat booster strategy in children. As a result, the CDC has removed COVID-19 vaccines from its recommended immunization schedule for healthy children and pregnant women.

While the Pfizer vaccine has been shown to be largely effective in preventing serious cases and hospitalizations in the general population, the same level of certainty does not extend to children. This is due to the lack of clinical data and studies specifically focused on this demographic. The available research on the Pfizer vaccine's effectiveness in reducing hospitalization risk primarily targets adults.

It is important to note that the absence of studies on reducing hospitalization risk in children does not imply that the Pfizer vaccine is unsafe for them. The vaccine has undergone rigorous testing and has been authorized for emergency use in children aged 6 months to 11 years by the CDC. However, the decision to vaccinate healthy children is now left to parental discretion, as health authorities recognize the lack of compelling evidence for routine vaccination in this demographic.

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