Health and Disease
by Peter Stair | May 6, 2008
Rising rates of testicular cancer, more frequent
genital defects, and deteriorating sperm quality
indicate that male reproductive health is declining
in many populations. Between 1960 and
2002, closely monitored men in Europe, the
United States, and New Zealand became two to
seven times more likely to suffer from testicular
cancer (see Table 1) and, on average, produced
about half as many sperm per milliliter of
semen.1 These changes have yet to be adequately
explained, but their rapid onset among younger
men suggests environmental disruptions during
early development are at least partly to blame.
Testicular cancer afflicts less than 1 percent
of the population, but it has become the most
common malignancy among men ages 20 to
34.2 The rate of testicular cancer among men
under 50 across northern Europe, Australia,
New Zealand, and the United States has been
increasing about 2–4 percent a year since the
1960s.3 Since rates of cryptorchidism (undescended
testicles) and hypospadias (shortened
urinary tracts) have risen simultaneously, some
specialists have identified a broader
“testicular dysgenesis syndrome” that
threatens male fertility.4 Men born with
testicular deformities and survivors of testicular
cancer tend to have more problems producing
enough healthy sperm to conceive children.5
The most recent analysis of several dozen
studies conducted primarily in Europe, North
America, and Australia since the 1930s found
that sperm density has fallen from 110–170
sperm per milliliter to just under 60.6 Studies
demonstrating such a broadly based decline in
sperm counts have been controversial, however,
because sperm quality can vary widely over the
course of a man’s life—rising during periods of
abstinence, for example, and declining during
the summer.7 Study samples have also often
come from men seeking vasectomies (who tend
to have higher than average sperm counts) or
from men in couples experiencing infertility
(who tend to have lower than average).8
Yet there is a consensus that sperm counts
vary by region and have fallen more in some
places than others. Men in New York City have
sperm counts 75 percent higher than men in
Columbia, Missouri, for example, while men in
Turku, Finland, have counts 25 percent higher
than men in Copenhagen, Denmark.9 Although
just one sperm is required to fertilize an egg,
researchers have identified sperm
concentrations of 40 per milliliter of semen as
the threshold below which men’s fertility
declines.10 According to a 2006 analysis, about
40 percent of men from Denmark and Norway
are below this level.11
In the United States, testicular cancer is
most common among urbanites in the northwestern
and central states and less likely in
New England and the South.12 In Europe, the
incidence is greatest in the region encompassing
Denmark and Switzerland and lowest in the
Baltic states, France, Italy, and Spain.13 In some
cases this inter-regional difference is sharp: men
born in Denmark or Norway are three times as
likely to have testicular cancer as men born in
Estonia or Finland.14
Some populations may be genetically more
vulnerable to reproductive disruption than others.
Testicular cancer is five times less common
among African Americans, for example, while
European men, on average, have higher sperm
counts than American or Japanese men.15 But
such differences do not explain the degree of
geographic variation in reproductive maladies:
although they are closely related in genetic backgrounds,
men in Denmark have notably lower
sperm counts that men in southern Sweden.16
Some lifestyle choices affect sperm counts.
Men who drink more alcohol or smoke more
cigarettes tend to have lower sperm counts.17
Overweightness, age, and other drug use have
also been associated with lower sperm quality.18
Cell phones may inhibit healthy sperm production:
a 2007 study found that men in Cleveland,
New Orleans, and Mumbai who used cell
phones longer than four hours each day had
sperm counts 25 percent lower than those who
never used them.19 Yet this relationship may be
confounded by other variables, such as sedentary
living.20
Exposure to chemicals that interfere with
sex hormones remains the prevailing explanation
for the increase in male reproductive disorders.21
Scientists have identified more than 50
synthetic chemicals that disrupt the endocrine
system and more than a dozen additional
suspects.22 Those most firmly associated with
reproductive disorders include dioxins, which
are released during paper pulp processing, coal
combustion, and waste incineration; polychlorinated
biphenyls, which are used for a range of
electrical, insulation, lubrication, and other
industrial purposes; and pesticides that are
commonly used in agriculture.23
Phthalates—a common plastic softener—
have also been linked with reproductive maladies.
24 A 2006 study in China found that workers
exposed to phthalates while manufacturing
polyvinyl chloride materials had lower levels of
testosterone.25 In a broader Massachusetts
study, men with higher levels of phthalate
metabolites in their blood had lower sperm
counts, lower sperm motility, and more sperm
deformities.26
Many compounds known to be disruptive to
reproductive development have been banned—
but only after years of widespread use. Between
1950 and 1975, for example, doctors prescribed
the estrogen-mimic diethylstilbestrol to 5 million
pregnant women, hoping to promote fetal
growth and prevent spontaneous abortions.27
Two decades passed before researchers realized
the sons of these women were more likely to
have smaller testicles, genital deformities, and
impaired sperm quality.28
Today more than 80,000 synthetic chemicals
are in production, and most have unknown
long-term effects.29 Acknowledging this, in
1996 the U.S. Environmental Protection Agency
initiated an Endocrine Disruption Screening
Program to evaluate more than 15,000 chemicals.
30 In Europe, similar concerns culminated
in the 2005 Prague Declaration on Endocrine
Disruption, which was signed by hundreds of
scientists from Europe and North America. It
warned of “serious risks” to men’s fertility and
urged more comprehensive monitoring of male
reproductive maladies.31
Clouding researchers’ ability to identify
harmful chemicals is the potential for some
chemicals to be safe in isolation but dangerous
in tandem with others. A 2006 study of tadpoles
found that only 4 percent died when they
were exposed to each of nine common pesticides
alone but 35 percent died from exposure
to a mixture of all nine.32 Since each person on
Earth now contains detectable levels of several
hundred synthetic chemicals, in varying proportions,
it is impossible to identify all the potentially
toxic chemical cocktails. Accordingly, the
Prague Declaration called for a “precautionary
approach” to regulating potentially disruptive
chemicals—an appeal to err on the side of caution
even in the absence of scientific consensus
about the sources of endocrine disruption.33
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by Mary Galinski and Esmeralda Meyer | May 6, 2008
The World Health Organization (WHO) reports
that 350–500 million people get malaria annually,
with at least 1 million of these cases resulting
in death.1 This is astounding for a disease
that by and large is preventable and treatable.2
Worse yet, new research indicates that these
numbers may be an underestimate.3
Malaria—which dates back to ancient
times—is endemic in 107 countries and territories
today, the result of a vicious cycle of transmission
of the Plasmodium parasite from female
anopheline mosquitoes to humans and back to
the mosquito.4 Breaking this cycle is the key to
controlling and eliminating the disease.5 Its
symptoms include intense fever, sweats, chills,
headache, and nausea.6 In serious cases, severe
anemia, organ failure, and coma are possible,
with death a major concern in the absence of
effective drug treatment and clinical care. Children,
pregnant woman, and non-immune adults
are the most vulnerable individuals.7
The direct costs for countries with the highest
incidence of malaria has been estimated at
$1.9 billion annually, while the global figure is
$3.2 billion.8 Lost work and school days and a
high level of morbidity affect individuals, families,
and communities worldwide on a grand
scale.9 A recent World Economic Forum
report on malaria drives home these
points and concludes that the private
sector can contribute significantly to malaria
control by investing in local programs.10
Today there is an unprecedented move to
scale up interdisciplinary approaches, coordination,
and the use of multiple proven malaria
control tools in sub-Saharan Africa, where 46
countries suffer from some of the highest levels
of malaria.11 To aid the process in Africa and
elsewhere, the new Malaria Atlas Project is developing
a global database on the prevalence of
this disease, taking into account the geographical
distribution patterns and transmission characteristics
of the two predominant species, P.
falciparum and P. vivax.12 (See Figure 1.)
In 1897, Sir Ronald Ross discovered that
malaria was transmitted by mosquitoes.13 From
1915 to 1952, the Rockefeller Foundation developed
projects to control malaria, and from
1955 to 1965 WHO led a Global Malaria Eradication
Campaign.14 Both organizations focused
on eliminating the mosquito vector, with notable
successes in the reduction of malaria.15
But the campaign, based on DDT spraying,
was abandoned soon after the publication of
Rachel Carson’s Silent Spring in 1962, which
led many to believe that DDT should not be
used—regardless of its public health benefits.16
Now the usefulness of DDT has again been
recognized, following two years of advocacy
that began in 1999 with an open letter by the
Malaria Foundation International that had 416
signatories from 63 countries.17 In December
2000, the importance of DDT for malaria control
was recognized in the Stockholm Convention
on Persistent Organic Pollutants.18 In 2006,
WHO gave DDT a clean bill of health, and
financial backing for DDT spraying resumed.19
At the time of World War II, chloroquine
became recognized as a cheap and effective
“wonder drug” to cure malaria, at 10¢ per treatment.
20 Yet chloroquine and all subsequent
malaria medications have developed resistance
or reduced sensitivity, especially for treating
the most lethal form of malaria, caused by P. falciparum.
21 Combination drugs are now recommended
to stop the spread of resistance.22
In 2004, a report in the medical journal The
Lancet claimed that it was medical malpractice
to use malaria drugs that had a high chance of
being ineffective.23 In turn, the Global Fund to
Fight AIDS, Tuberculosis and Malaria—the
major funding source today for malaria drugs—
vowed to support only the use of reliable antimalarial
drugs and to seek more than $1 billion
from donors to pay for artemisinin-based
combination therapy (ACT).24 The Fund has
determined that $2.9 billion is needed in 2007
to use all available means to control malaria,
yet only about $300 million is currently allocated.
25 Today, experts are working to produce
more artemisinin, to develop adequate amounts
of effective ACT, to manage and reduce the high
cost of this drug, and to develop avenues for its
effective distribution and use.26 An intermittent
therapy for pregnant women is also recognized
as a priority.27 With the higher cost of current
malaria treatments, the confirmation
of malaria diagnosis by
microscopy or rapid diagnostic
tests is crucial for control and
prevention strategies.28
Long-lasting insecticidetreated
bed nets are now being
promoted as a way to prevent
malaria through the distribution
of millions of nets in Africa and
as a tool to gain the attention of
the public and raise new funds.29
Sleeping with the protection of
these nets will help prevent the
disease.30 While it is not a total
solution, it is a reasonable line
of attack in light of today’s interdisciplinary
approach to combating
malaria.31
Fifteen years ago malaria received little if any
media attention worldwide. Modern approaches
to malaria advocacy and education began with
the 1995 launch of the Malaria Foundation
International’s Web site.32 Dozens of organizations
and initiatives are now rallying around
this cause.33 While funding is far from adequate
and malaria is still not covered well in the
media, attention has been increasing steadily.34
Control measures are being implemented in
Africa with increasingly large funds from the Bill
& Melinda Gates Foundation (over $765 million
since 1999 for malaria research and control), the
World Bank ($500 million promised in 2000),
and the President’s Malaria Initiative ($1.2 billion
pledged by the U.S. government in 2005).35
Some successes in malaria control have been
noted. The Roll Back Malaria program in Eritrea
evaluated the use of insecticide-treated
bed nets, DDT spraying, and case management
between 2000 and 2004 and reported an 84-
percent decline in malaria morbidity and a 40-
percent drop in case fatality.36 In another study,
researchers found that high coverage with ACT
was the most cost-effective strategy for malaria
control in sub-Saharan Africa.37
To encourage a greater commitment, in 2005
the Malaria R&D Alliance—a global coalition
of research and development organizations—
surveyed malaria research and development
investments.38 It found that only $323 million
was dedicated to malaria research in 2004, less
than 0.3 percent of total health research spending
worldwide.39
More than 90 percent of health research
resources are spent on diseases that affect just
10 percent of the world’s population, while
research is badly needed on new malaria drugs,
on development of malaria vaccines, and on
ways to use and monitor malaria control tools
effectively.40 Many potential malaria vaccines
are being developed, although none have
reached the market to date.41 But knowledge
about malaria genome sequences, modern technologies,
and concerted efforts provide hope
that an effective vaccine will be available in
the future.42
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People at Risk of Malaria, 2005
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by Lindsay Hower Jordan | May 6, 2008
As of December 2006, some 39.5 million people
around the world were living with HIV, the
virus that causes AIDS—37.2 million of them
were adults, with an estimated 17.7 million
women over the age of 15 carrying the infection.
1 Some 4.3 million people were newly
infected with HIV in 2006, with a little more
than 500,000 of those new infections occurring
in people under the age of 15.2 In 2006, 2.9
million people died from AIDS.3
In Western Europe, HIV infection rates
increased sharply in the last eight years, from
42 cases per million people in 1998 to 74 cases
per million in 2006.4 Around the Baltic region,
the high HIV infection trend that characterized
the turn of the twenty-first century there
appears to be abating, particularly in Latvia and
Estonia.5 South and Southeast Asia is home to
7.8 million infected individuals, an 8-percent
increase from 7.2 million in 2004; in East Asia,
the figure is around 750,000 people, up from
620,000 in 2004; and in Latin America, the
infected total is around 1.7 million, up from 1.5
million in 2004.6
Sub-Saharan Africa is home to nearly two
thirds of people worldwide living with HIV.7
(See Figure 1.) In this region, there were 2.8
million newly infected individuals in 2006, up
slightly from 2.6 million just two years earlier.8
At the end of 2006, UNAIDS estimated that
24.7 million sub-Saharan Africans are infected
with HIV, an increase of 1.1 million since
2004.9 Seventy-two percent of deaths due to
AIDS occur in sub-Saharan Africa.10
Modes of HIV transmission vary widely
by region. For example, injecting drug users
account for 67 percent of all HIV
cases in Eastern Europe and Central
Asia.11 In South and Southeast Asia,
in contrast, they account for 22 percent of
cases, while 49 percent of victims there are
infected through commercial sex work (8 percent
are sex workers; 41 percent are clients).12
Men having sex with men accounted for 4
percent of HIV cases in Eastern Europe and
Central Asia, 5 percent in South and Southeast
Asia, and 26 percent in Latin America.13
In 2006 there were more women infected
with HIV in every region of the world than ever
before.14 Women are at particularly high risk in
countries with rampant infection rates, since
they are not traditionally in a position of power
or decisionmaking in their sexual relationships.
In the Caribbean, North Africa, Oceania, and
the Middle East, almost half the adults infected
with HIV are women age 15 or older.15
In sub-Saharan Africa, women outnumber
men in infection estimates, accounting for up to
60 percent of people living with HIV.16 According
to Ludfine Anyango, national HIV/AIDS
coordinator at Action Kenya-International,
“many women cannot even choose when to
have sex or not. Many cannot ask their husbands
to use a condom because in addition to
being thought as unfaithful, they fear being
beaten. The woman then has no choice but
to continue having unprotected sex with her
spouse.”17 Street violence likewise exposes
female sex workers to high risk of HIV infection
for the same reasons, according to Ros
Sokunthy of Women’s Agenda for Change, a
Cambodia-based organization fighting to protect
women’s rights, including those of female
sex workers.18
In 70 countries surveyed, use of testing and
counseling services has quadrupled since 2001,
from 4 million to 16.5 million people in 2005.19
In Sudan, where HIV prevalence in North
Africa is at its highest, 350,000 people—1.6
percent of the country’s population—were living
with HIV in 2005.20 Current knowledge of
the benefits of contraception and of how HIV
is transmitted is pitifully poor there: in a 2005
survey of police officers in Khartoum, only 2
percent of the men knew that condoms could
prevent transmission.21 Certain countries,
including Iran, have implemented clean syringe
and methadone operations as well as government-
funded clinics that offer free HIV counseling,
testing, and treatment.22
From 1996 to 2005, funding for HIV/AIDS
assistance efforts in low- and middle-income
countries increased from $300 million to $8.3
billion.23 But current trends in existing pledges
may indicate the funding is waning, with
pledges totaling just $8.9 billion in 2006 and
$10 billion in 2007.24 The
United Nations has projected
needs at $14.9 billion in 2006,
$18.1 billion in 2007, and
$22.1 billion in 2008, highlighting
a sustained gap
between current funds and
future needs over the next few
years.25 In August 2006, the
Bill & Melinda Gates Foundation
committed $500 million
over five years to the Global
Fund to Fight AIDS, Tuberculosis
and Malaria—the largest
gift to support AIDS and
other disease research from a
nongovernmental source since
the fund was established.26
In 2000, after settling a lawsuit
by the South African government on patent
rights, the leading producers of HIV medicines
established the Accelerating Access Initiative
(AAI) in collaboration with five U.N. agencies,
including UNAIDS, to provide more anti-retroviral
medicines at lower costs.27 An AAI report
in June 2003 indicated that the number of
Africans receiving treatment under this
initiative was eight times higher than when the
program began in 2000, totaling approximately
75,000.28 By March 2005, AAI was reaching
more than 427,000 patients.29
Pharmaceutical companies have made considerable
strides in working with corporate firms
and national governments to craft national
efforts that address HIV infection and alleviate
stress from limited access to drugs.30 Public-private
partnerships are an encouraging development,
such as Johnson & Johnson’s royalty-free
collaboration with the International Partnership
for Microbicides—a cross-sector partnership
that aims to develop and distribute its recently
developed compound TMC120 as an experimental
vaginal microbicide.31
Generic anti-retroviral drugs are beginning
to dominate the global consumer drug market.
In 2006, preliminary statistics suggested that 70
percent of anti-retrovirals in Nigeria, Haiti, and
Zambia were generic.32 This influx is primarily
the result of the U.S. Food and Drug Administration’s
approval of 29 generic AIDS drugs.33
In the 1990s, Brazil had an HIV rate that
rivaled South Africa’s, but since 1996 it has cut
the infection rate to 0.6 percent of the adult
population—including an 80-percent reduction
in HIV-related hospitalization—by becoming
the first country to offer universal treatment.34
But as HIV patients build resistance to old
drugs and as drug companies refuse to offer
contracts for newer generic versions, Brazil was
forced to spend 75 percent more on anti-retrovirals
between 2004 and 2006.35 Although the
government has negotiated with drug companies
for the cheapest price outside of Africa, it
still has to pay $17,000 a year per patient—a
jarring price tag for a government accustomed
to buying older generic drugs for hundreds of
dollars per patient annually.36
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People Living With HIV, By Region, 2004 and 2006
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