Your Herd is Larger Than You Think: Why Global Vaccine Equity is Crucial

Herd Immunity. It is the new buzzword of the pandemic. It follows closely behind social distancing in its popularity in current American lexicon. With most efforts focusing on vaccinating people across America, we are at risk of falling into the trap of localized thinking. We are forgetting about global herd immunity. Sadly, the recent devastating COVID-19 outbreak in India has brought serious concerns about global herd immunity to the forefront.

What is Herd Immunity?

Herd immunity refers to the majority of a population developing protection from an infectious disease or virus, thereby liming the number of viable hosts in which the virus can propagate and spread. This can develop either from recovering from an exposure or from vaccination, both of which teach your immune system how to respond to future exposures. The percentage of the population who need to be immune to reach herd immunity depends on the pathogen but typically falls within the 50 to 90 percent range. With COVID-19, the current estimated threshold lies at around 80 percent of the population.

The Path Toward Herd Immunity in the United States

As of mid-April, nearly 1 in 4 people (23.6 percent) have been fully vaccinated nationwide. Massachusetts is doing even better, with 27.5 percent of the population fully vaccinated, and nearly half of the population (46.2 percent) receiving at least one dose, with some regional variation.

This is great progress. The United States is on track toward herd immunity, albeit with persistent concerns about vaccine hesitancy and uncertainty about the possibility of waning immunity.

Implications of Global Herd Immunity

Without global herd immunity, the pandemic can never truly come to an end. Based on the current rollout of the COVID-19 vaccine, it looks as though high-income countries could reach herd immunity near the end of 2021. Middle-income countries will be vaccinating their residents into 2022. Low-income countries will continue waiting into 2023. This inequity is clear, and all global citizens will suffer for it.

This disparity in access exists in part because wealthier countries are buying a surplus of vaccines to reach national herd immunity more quickly, something the leader of the WHO has labeled a “moral failure.” Despite only representing 19 percent of the global population, high-income countries have purchased 54 percent of the doses. With variants developing quickly – we need to reach global herd immunity before the virus has a chance to mutate even more, rendering our current tools ineffective. For example, in Massachusetts we are experiencing an outbreak of the P.1 variant primarily in Cape Cod. The WHO is currently evaluating the efficacy of existing vaccines against developing variants, so we still don’t know for sure the level at which we are protected.

Enter: COVAX

Designed as a collaboration between nations and administered through the WHO, UNICEF, the Coalition for Epidemic Preparedness Innovations (CEPI), and Gavi, COVAX aims to distribute vaccines more equitably to countries far sooner than they would receive them otherwise.

COVAX is the global health attempt to address global herd immunity. The theory is that if enough people are vaccinated globally, the virus will lack sufficient viable hosts to develop and mutate, effectively ending the pandemic. So far, COVAX has raised $6 billion, with the Biden Administration promising an initial $2 billion, with another $2 billion set aside for 2021 and 2022. According to WHO, COVAX has accelerated vaccinations in Ghana, Côte d’Ivoire, India, and South Korea. While these efforts are underway, proponents and critics of COVAX are pushing for more transparency regarding vaccine manufacturing, allocation, and pricing, as a full global distribution plan has yet to be released.

The Kaiser Family Foundation estimates that while the total purchased doses in the world could vaccinate 4 out of 5 adults globally, low- and middle- income countries only have enough doses to vaccinate about a third of their populations, while high-income countries could vaccinate their adult populations more than twice over. Even if COVAX reallocates all their doses to these low- and middle-income countries, they still wouldn’t reach the halfway mark.

Part of the problem – and potentially part of the solution – is to share the patent for the vaccine. Manufacturers globally claim that their primary roadblock is patent licensing deals, prohibiting them from supplementing current production rates.

The majority of COVAX doses have been produced in India, which has exported over 60.5 million doses to distribute globally. The Serum Institute of India has been a mass producer of the AstraZeneca vaccine – one of the few with shared licenses – and has undoubtedly accelerated the pace of global vaccinations. It has also served as a cautionary tale as to why COVAX is necessary.

While imperfect, COVAX has demonstrated its value. AstraZeneca’s vaccine manufacturing was held up due to a surge in cases in India that has surpassed previous records of new infections, skyrocketing to 350,000 cases per day. This abrupt increase in new infections led Indian officials to halt vaccine exportation in favor of inoculating their own at-risk population. This also slowed down vaccine efforts in Africa as they had been supplied by India.

As these decisions were being weighed, the COVAX program kicked in to coordinate 65 million doses from alternative sources. The United States has also promised to fund further manufacturing of the Johnson & Johnson vaccine through the Indian firm Biological E, though that vaccine has generated concerns of its own.

The Lesson

The COVID-19 virus will likely continue to mutate, and we must use everything in our power to reduce the harm mutations might cause. The best way to stop the spread is to decrease potential disease vectors through immunization, and this must be done on a global level.

COVAX is a great place to start for ensuring global vaccine equity. We have seen how it can help ameliorate damages when sudden roadblocks occur, like the surge in India. However, we need to do more to guarantee vaccine equity across the world. It starts with rich countries like the United States stepping out of the way and prioritizing people over profits.