Pandemic prevention is the organization and management of preventive measures against pandemics.
Those include measures to reduce causes of new infectious diseases and
measures to prevent outbreaks and epidemics from becoming pandemics.
History
The 2003 SARS-CoV virus was prevented from causing a pandemic. Rapid action by national and international health authorities such as the World Health Organization
helped to slow transmission and eventually broke the chain of
transmission, which ended the localized epidemics before they could
become a pandemic. However, the disease has not been eradicated and
could re-emerge. This warrants monitoring and reporting of suspicious
cases of atypical pneumonia.
Effective isolation of patients was enough to control spread because
infected individuals usually not transmitting the virus until several
days after symptoms began and were most infectious only after developing
severe symptoms.
Measures
Infrastructure and international development
Robust, collaborating public health systems may be required to be able stop contagion promptly.
After an outbreak there is a certain window of time during which a
pandemic can still be stopped by the competent authorities isolating the
first infected and/or fighting the pathogen. A good global
infrastructure, consequent information exchange, short ways in bureaucracy and effective, targeted treatment measures can be prepared. 2012 it has been proposed to consider pandemic prevention as an aspect of international development in terms of health-care infrastructure and changes to the pathogen-related dynamics between humans and their environment including animals.
Often local authority carers or doctors in Africa, Asia or Latin
America register uncommon accumulations (or clusterings) of symptoms but
lack options for more detailed investigations.
Scientists state that "research relevant to countries with weaker
surveillance, lab facilities and health systems should be prioritized"
and that "in those regions, vaccine supply routes should not rely on
refrigeration, and diagnostics should be available at the point of
care".
Technologies
Pathogen detection and prediction
In
a 2012 study it is claimed that "new mathematical modelling,
diagnostic, communications, and informatics technologies can identify
and report hitherto unknown microbes in other species, and thus new
risk assessment approaches are needed to identify microbes most likely
to cause human disease". The study investigates challenges in moving the
global pandemic strategy from response to pre-emption. Some scientists are screening blood samples from wildlife for new viruses. The international Global Virome Project
(GVP) aims to identify the causes of fatal new diseases before
emergence in human hosts by genetically characterizing viruses found in
wild animals. Edward Rubin
notes that after sufficient data has been gathered artificial
intelligence could be used to identify common features and develop
countermeasures and vaccines against whole categories of viruses.[10] It might be possible to predict viral evolution using machine learning. Funding for the United States' PREDICT government research program that sought to identify animal pathogens that might infect humans and to prevent new pandemics was cut in 2019. Funding for United States' CDC
programs that trained workers in outbreak detection and strengthened
laboratory and emergency response systems in countries where disease
risks are greatest to stop outbreaks at the source was cut by 80% in
2018.
CRISPR-based immune subsystems
In March 2020 scientists of Stanford University presented a CRISPR-based system, called PAC-MAN (Prophylactic Antiviral Crispr in huMAN cells), that can find and destroy viruses in vitro. However, they weren't able to test PAC-MAN on the actual SARS-CoV-2, use a targeting-mechanism that uses only a very limited RNA-region, haven't developed a system to deliver it into human cells and would need a lot of time until another version of it or a potential successor system might pass clinical trials. In the study published as a preprint they write that it could be used prophylactically as well as therapeutically. The CRISPR-Cas13d-based system could be agnostic to which virus it's fighting so novel viruses would only require a small change.
In an editorial published in February 2020 another group of scientists
claimed that they have implemented a flexible and efficient approach for
targeting RNA with CRISPR-Cas13d which they have put under review and
propose that the system can be used to also target SARS-CoV-2 in
specific. There have also been earlier successful efforts in fighting viruses with CRISPR-based technology in human cells.
Testing and containment
A SARS-CoV-2 laboratory test kit by the CDC
Timely use and development of quick testing systems for novel virus in combination with other measures might make it possible to end transmission lines of outbreaks before they become pandemics. A high discovery-rate is important for tests. For instance this is the reason why no thermal scanners with a low discovery-rate were used in airports for containment during the 2009 swine flu pandemic. The German program InfectControl 2020 seeks to develop strategies for prevention, early recognition and control of infectious diseases.
In one of its projects "HyFly" partners of industry and research work
on strategies to contain chains of transmission in air traffic, to
establish preventive countermeasures and to create concrete
recommendations for actions of airport operators and airline companies.
One approach of the project is to detect infections without
molecular-biological methods during passenger screening. For this
researchers of the Fraunhofer-Institut for cell therapy and immunology are developing a non-invasive procedure based on ion-mobility spectrometry (IMS).
Surveillance and mapping
Monitoring people who are exposed to animals in viral hotspots – including via virus monitoring stations – can register viruses at the moment they enter human populations - this might enable prevention of pandemics.
The most important transmission pathways often vary per underlying
driver of emerging infectious diseases such as the vector-borne pathway
and direct animal contact for land-use change – the leading driver for
emerging zoonoses by number of emergence events as defined by Jones et al. (2008). Zoonoses account for 75% of the reviewed 1415 species of infectious organisms known to be pathogenic to humans until 2001. Genomics
could be used to precisely monitor virus evolution and transmission in
real time across large, diverse populations by combining pathogen
genomics with data about host genetics and about the unique transcriptional signature of infection.
The "Surveillance, Outbreak Response Management and Analysis System"
(SORMAS) of the German Helmholtz-Zentrum für Infektionsforschung (HZI)
and Deutsches Zentrum für Infektionsforschung (DZIF), who collaborate
with Nigerian researchers, gathers and analyzes data during an outbreak,
detects potential threats and allows to initiate protective measures
early. It's meant specifically for poorer regions and has been used for
the fight against a monkeypox outbreak in Nigeria.
Policy and economics
A 2014 analysis asserts that "the window of opportunity to deal with pandemics as a global community is within the next 27 years. Pandemic prevention therefore should be a critical health policy issue for the current generation of scientists and policymakers to address.
A 2007 study warns that "the presence of a large reservoir of
SARS-CoV-like viruses in horseshoe bats, together with the culture of
eating exotic mammals in southern China, is a time bomb. The possibility
of the reemergence of SARS and other novel viruses from animals or
laboratories and therefore the need for preparedness should not be
ignored".
The US' National Security Council Directorate for Global Health
Security and Biodefense, which worked on preparing for the next disease
outbreak and preventing it from becoming an epidemic or pandemic, was
closed in 2018.
Environmental policy and economics
Some experts link pandemic prevention with environmental policy and caution that environmental destruction as well as climate change drives wildlife to live close to people. For instance the WHO projects that climate change will also affect infectious disease occurrence.
A 2016 study reviews literature on the evidences for the impact of
climate change on human infectious disease, suggests a number of
proactive measures for controlling health impacts of climate change and
finds that climate change impacts human infectious disease via
alterations to pathogen, host and transmission. Studies have shown that the risk of disease outbreaks can increase substantially after forests are cleared.
Stanford biological anthropologist James Holland Jones notes that
humanity has "engineer[ed] a world where emerging infectious diseases
are both more likely and more likely to be consequential", referring to
the modern world's prevalent highly mobile lifestyles, increasingly
dense cities, various kinds of human interactions with wildlife and
alterations of the natural world.
Biotechnology research and development regulation
Toby Ord
puts into question whether the current public health and international
conventions, and self-regulation by biotechnology companies and the
scientific community are adequate. In the context of the 2019–2020 coronavirus pandemic Neal Baer writes that the "public, scientists, lawmakers, and others" "need to have thoughtful conversations about gene editing now".
Food markets and wild animal trade
Fowl cages at wet market in Shenzhen, China
In January 2020 during the SARS-CoV 2 outbreak experts in and outside China warned that wild animal markets, where the virus originated from, should be banned worldwide. On January 26 China banned the trade of wild animals until the end of the coronavirus epidemic at the time. On February 24 China announced a permanent ban on wildlife trade and consumption with some exceptions. Some scientists point out that banning informal wet markets
worldwide isn't the appropriate solution as fridges aren't available in
many places and because much of the food for Africa and Asia is
provided through such traditional markets. Some also caution that simple
bans may force traders underground, where they may pay less attention
to hygiene and some state that it's wild animals rather than farmed
animals that are the natural hosts of many viruses.
International coordination
The Global Health Security Agenda
(GHSA) a network of countries, international organizations, NGOs and
companies that aim to improve the world's ability to prevent, detect,
and respond to infectious diseases. Sixty-seven countries have signed
onto the GHSA framework. Funding for the GHSA has been reduced since the launch in 2014, both in the US and globally. In a 2018 lecture in Boston Bill Gates called for a global effort to build a comprehensive pandemic preparedness and response system.
Containment and prevention by artificial induction of immunity and/or biocides
Outbreaks could be contained or delayed – to enable other
containment-measures – or prevented by artificial induction of immunity
and/or biocides in combination with other measures that include
prediction or early detection of infectious human diseases.
In a preprint published on March 24, 2020 researchers suggested that the unique transcriptional signature of SARS-CoV-2 in the human immune system may be responsible for the development of COVID-19: SARS-CoV-2 did not induce the antiviral genes that code for type I and type III interferons. This could be relevant for the development or repurposing of treatments.
Vaccination
Development and provision of new vaccines usually takes years. The Coalition for Epidemic Preparedness Innovations, which was launched in 2017, works on reducing the time of vaccine-development.
Culling
Experts warned that depleting the numbers of species by culling to forestall human infections reduces genetic diversity
and thereby puts future generations of the animals as well as people at
risk while others contend that it's still the best, practical way to
contain a virus of livestock.
Prevention versus mitigation
Pandemic prevention seeks to prevent pandemics while mitigation of
pandemics seeks to reduce their severity and negative impacts. Some have
called for a shift from a treatment-oriented society to a
prevention-oriented one.
Authors of a 2010 study write that contemporary "global disease control
focuses almost exclusively on responding to pandemics after they have
already spread globally" and argue that the "wait-and-respond approach
is not sufficient and that the development of systems to prevent novel
pandemics before they are established should be considered imperative to
human health". Nathan Wolfe
criticizes that "our current global public health strategies are
reminiscent of cardiology in the 1950s when doctors focused solely on
responding to heart attacks and ignored the whole idea of prevention".
