16 | New Scientist | 26 October 2019Analysis Infectious diseasesFRUIT bats and mosquitoes
rarely feature in discussions of
the potential impacts of major
environmental changes such as
deforestation and climate change.
But two studies last week showed
how environmental destruction
could lead to a greater spread
of deadly diseases to people via
animals such as these, with dire
consequences for public health.
The 2016 Ebola outbreak
in West Africa killed more than
11,000 people directly, and
knock-on effects, such as diverting
medical resources away from
other conditions, led to thousands
more deaths. Worryingly, climate
change could cause a rise in Ebola
rates over the next 50 years, say
UK and US researchers who have
created a predictive model for the
disease. They successfully tested
it on past outbreaks of the virus.
In the worst-case warming
scenarios, the model shows areas
possibly affected by “spillovers” of
Ebola – when the virus jumps from
animal to human – will rise by
nearly 15 per cent compared with
today (Nature, doi.org/dcx2). That
may expose new parts of western
and central Africa to the disease.“By changing the environment,
we are going to directly impact
our health,” says David Redding
at University College London. One
way in which climate change will
affect the risk of diseases such
as Ebola spreading is by making
new areas into suitable homes
for disease-carrying species. For
example, if the trees that fruit bats,
believed to be a reservoir for the
Ebola virus, rely on can grow in
a new area, the bats can follow.Global warming isn’t the only
environmental change that could
increase disease risk. Clearance
of the Amazon rainforest may
also increase the spread of
malaria, suggests research by
Andrew MacDonald and Erin
Mordecai at Stanford University
in California (PNAS, doi.org/dcxz).
Their analysis of 13 years of
malaria cases and satellite data for
the Brazilian Amazon found that
a 10 per cent rise in deforestation
was associated with a 3.3 percent increase in malaria cases
there – almost 10,000 extra
a year. That is probably because
more people end up settling closer
to mosquito-infested areas and
are more likely to get bitten, while
logging creates more mosquito-
friendly habitats.
The relationship also seems to
hold in reverse: as malaria rises,
economic activity, and hence
deforestation, slows. MacDonald
says that effect will never halt tree
loss though, so the world needs to
pay attention to greater disease
risk from environmental damage.
“I think the sorts of large
environmental changes we are
seeing today, including climate
and land use change, have a high
potential to lead to changes in
health outcomes, including the
transmission of infectious
diseases,” he says.
“Climate change definitely has
an impact on infectious diseases,”
says Elke Hertig at the University of
Augsburg, Germany. But whether
the impacts are good or bad will
always hinge on local factors, she
says. In her own research, Hertig
has found that while warmer
temperatures will help malaria-
carrying mosquito species spread
northwards across Europe, some
Mediterranean areas will become
too hot and dry for them.
Daniel Bausch, who is part of
the UK’s rapid disease response
unit, says we should take the
influence of environmental change
on disease risk seriously. However,
the strength of healthcare systems
remains key to determining future
outbreaks of disease, he says.
“We need the modelling and the
ecology research to understand
the high risk. But then we need
to act on that.” ❚JUAN CARLOS MUNOZ/GETTY IMAGES
News
The Ebola virus is
thought to jump from
fruit bats to people15%
increase in areas where Ebola
may erupt in a warmer worldWrecking the planet could worsen outbreaks Both
malaria and Ebola could spread further than before due to
deforestation and climate change, reports Adam VaughanHealth dataAdam VaughanGOOGLE will receive five years’
worth of sensitive National Health
Service (NHS) patient records under
the terms of a deal signed last
month, despite controversy over
similar contracts in the past.
The extent to which patient data
was shared between an NHS trust in
England and AI company DeepMind
was first revealed by New Scientist
in 2016. The data watchdog later
ruled that the deal failed to comply
with the law because of failures
to inform patients.
However, other NHS trusts
went on to sign agreements with
DeepMind. Last month, five of them
chose to transfer their contracts
over to Google Health after it
absorbed part of DeepMind, which
is owned by the same parent
company – Alphabet – as Google.
One NHS trust decided against it.
Although Google says there is
no material difference in the content
of the deals, DeepMind Health
chose to publish its contracts with
the NHS – something that is no
longer the case with Google.
However, a contract released
in response to a freedom of
information request by New
Scientist shows that Taunton and
Somerset NHS Foundation Trust
will grant Google five years’ worth
of anonymised historical data on
patients. In a previous arrangement
between DeepMind Health and the
Royal Free NHS Trust, anonymised
data included patients’ medical
history, diagnoses, treatment dates
and ethnic background.
“This deal shows just how little
has changed for one of the most
controversial NHS data projects
of the last half decade,” says
Sam Smith at campaign group
MedConfidential. He asks why
the contract suggests data will
be copied in bulk, rather than
accessed using an international
standard used for sharing medical
records, known as FHIR. ❚Details of NHS data
deal with Google
revealed