Friday, November 12, 2010

Children, Not Adults, Spread Whooping Cough

A new study on whooping cough outbreaks and how social patterns affect transmission suggests that blanket vaccination campaigns that target teens and adults could be a waste of time, as children largely spread the disease among themselves.

The findings contradict the common idea that infected adults are behind outbreaks of whooping cough, a contagious disease caused by the bacterium Bordetella pertussis.

A US advisory panel last month recommended that adults over 65 get a booster vaccine for tetanus, diphtheria and whooping cough to protect infants that are too young to be vaccinated.

But according to research by Pejman Rohani and colleagues at the University of Michigan, older people may not be the culprit.

Whooping cough infects 30 to 50 million people a year around the world and kills around 300,000, mostly children in developing countries.

Developed countries have regular outbreaks, including one in California that has affected more than 6,000 people and killed at least 10 infants, said the US Centers for Disease Control and Prevention (CDC).

The researchers used a situation that occurred in Sweden to study the effects of social interactions around the spread of whooping cough.

Sweden stopped its whooping cough vaccination program in 1979 because of safety concerns, and did not resume routine vaccinations for 17 years. But during that time, health officials continued to track cases of whooping cough by age group.

“We took advantage of an unplanned natural experiment,” Rohani told Reuters in a telephone interview.

The team compared this to a 2008 study of more than 7,000 people from eight European countries that tracked social contacts by age. They used a computer model to see how social contacts affected the spread of the disease.

The team discovered that once Sweden resumed vaccinating young children, there was a big drop in the number of whooping cough cases in all age groups except teenagers. They found that with social mixing patterns, children mostly interact with other children and are unlikely to be infected by adults.

“Infant immunization produces a protective effect for other children, who are likely to be mixing with other infants,” the team wrote. Infected adults did not play a big role in spreading the disease to children.

The UM study shows that, overall, “the role of adults in transmission is minimal,” and that blanket booster-vaccinations of adults would unlikely be an efficient strategy for controlling whooping cough, said Aaron King, an assistant professor of ecology and evolutionary biology with a joint appointment in mathematics, who was part of the study.

The researchers stressed that because the study used incidence data from Sweden, results could vary with any incidences in the United States, where infant vaccination compliance rates are lower and the population is much more diverse. “We need similar analyses for the United States,” said Rohani.

The study makes two strong conclusions, King said. “The first point is that we see strong evidence for the efficacy of vaccination directed at children when compliance is high. The second is that better knowledge of actual contact patterns among age groups is crucial for the design of more effective and economical vaccination strategies.”

Rohani said more studies would need to be conducted to explain how social networks affect regional disease outbreaks. But looking at social networks is another way to better understand how infectious diseases are spread and could save time and the expense of mass vaccinations that may not work.

The findings from the study were published Thursday in the journal Science.

G20 leaders agree: Let’s put off decisions until next year

The world’s biggest economies avoided a breakdown in cooperation at a G20 summit here by agreeing to put off decisions on issues dividing leading countries until next year.

“These things didn’t happen overnight, they’re not going to be fixed overnight,” Prime Minister Stephen Harper said of the intractable global trade and investment patterns that are hampering economic growth and pitting fast-growing emerging economies against debt-burdened industrial nations.Leaders of the G20, which took shape in 2008 to fight the recession, pledged to address these irritants, but failed to agree on a mutually-acceptable system for identifying economic imbalances that countries must fix for the good of the international economy. Canada will lead a G20 working group that will try in 2011 to set out guidelines that member nations must live up to.“I think it’s fair to say we did not resolve those issues here,” said Harper, whose mood after the two-day meeting in Seoul was decidedly less buoyant than after leaders agreed in Toronto in June to cooperate on economic policy in the wake of the recession.
“We are keeping things at least on a path that is viable,” he told reporters. But “moving forward, G20 credibility does depend on showing results and achieving concrete action.”
Underneath the tensions that emerged in Seoul are disagreements over how to address global imbalances in trade and investment flows that contributed to the recent recession. The United States is looking to exporting nations like China to adjust their economic policies to increase domestic demand at home rather than relying on the American consumer. In particular, U.S. President Barack Obama wants China to scrap its policy of keeping its currency, the yuan, artificially low on exchange markets, which the U.S. says hurts American exporters by giving Chinese companies an unfair price advantage.
G20 leaders agreed on the need for countries to refrain from keeping their currencies at artificially low rates but there was no mechanism to back up the principle.
Obama welcomed the leaders’ call for joint action but again implored China to let its currency float in keeping with market forces. “China spends enormous amounts of money intervening in the market to keep (its currency) undervalued,” Obama said at a news conference. He said the communiqué reflected the G20’s belief that “letting currencies reflect market fundamentals. . . is the best way to assure that everybody benefits from trade rather than just some” and he expressed hope that China would gradually reform its currency policy.
China has so far dismissed Obama’s demands, saying the U.S. needs to get its own financial house in order to cure its economic woes.
Without the pressure of an impending global economic calamity, G20 nations have found it harder to put aside their individual differences and ambitions to pursue strategies of mutual benefit. “Risks remain,” the joint communiqué said. “Some of us are experiencing strong growth, while others face high levels of unemployment and sluggish recovery. Uneven growth and widening imbalances are fuelling the temptation to diverge from global solutions into uncoordinated actions.”
There are fears that aggressive use of currency settings by countries trying to improve their export sales abroad could lead to a currency war that could badly hurt the world economy.
The G20 did agree on banking reforms intended to prevent a financial collapse such as the one that spawned the recent recession. And leaders threw their weight behind efforts to reduce international trade barriers under the long-stalled Doha round of global trade negotiations.
At his wrap-up news conference here, Harper said that he does not need the approval of Parliament to extend Canada’s military mission in Afghanistan because it will be a training mission not involving combat.
“My position is, if you are going to put troops into combat, into a war situation, I do think, for the sake of legitimacy. . . the government does require the support of Parliament. But when we’re talking simply about technical or training missions, I think that is something the executive can do on its own,” he told reporters. He noted, however, that the Liberals have indicated that they favour a training mission. “If they have any specific ideas they want to share, I’m not resistant to having debates on that matter in the House of Commons,” Harper added.

Pakistani stocks, o/n rates end lower; rupee weakens

Pakistani stocks ended lower on Friday following a suicide car bomb attack the previous day in the country's commercial hub, dealers said.

At least 15 people were killed and 100 injured in a suspected Taliban suicide car bomb attack on Thursday at a security compound in Karachi where militants were held. [ID:nLDE6AA21L]

The Karachi Stock Exchange's benchmark 100-share index .KSE ended 0.29 percent, or 31.22 points, lower at 10,874.02.

Volume fell to 97.52 million shares, compared with 125.22 million traded on Thursday.

"The blast weighed on the market. However, the prospect of a potential approval of a leveraged product got some local institutions to step in to support the market towards the end," said Asad Iqbal, chief investment officer at Faysal Asset Management Ltd.

The approval of margin buying is expected this month.

In the currency market, the rupee PKR= ended weaker at 85.63/70 to the dollar, compared with Thursday's close of 85.37/42 due to higher imports payments, especially of oil, dealers said.

In the money market, overnight rates fell to end between 11.5 percent and 12 percent, compared with Thursday's close of 13 percent despite scheduled outflows of 9.3 billion rupees as dealers said there was increased liquidity in the interbank market.

Dealers said they were waiting for the treasury bill auction which is scheduled for Nov. 15, instead of Nov. 17 due to holidays

Pakistani stocks, o/n rates end lower; rupee weakens

Pakistani stocks ended lower on Friday following a suicide car bomb attack the previous day in the country's commercial hub, dealers said.

At least 15 people were killed and 100 injured in a suspected Taliban suicide car bomb attack on Thursday at a security compound in Karachi where militants were held. [ID:nLDE6AA21L]

The Karachi Stock Exchange's benchmark 100-share index .KSE ended 0.29 percent, or 31.22 points, lower at 10,874.02.

Volume fell to 97.52 million shares, compared with 125.22 million traded on Thursday.

"The blast weighed on the market. However, the prospect of a potential approval of a leveraged product got some local institutions to step in to support the market towards the end," said Asad Iqbal, chief investment officer at Faysal Asset Management Ltd.

The approval of margin buying is expected this month.

In the currency market, the rupee PKR= ended weaker at 85.63/70 to the dollar, compared with Thursday's close of 85.37/42 due to higher imports payments, especially of oil, dealers said.

In the money market, overnight rates fell to end between 11.5 percent and 12 percent, compared with Thursday's close of 13 percent despite scheduled outflows of 9.3 billion rupees as dealers said there was increased liquidity in the interbank market.

Dealers said they were waiting for the treasury bill auction which is scheduled for Nov. 15, instead of Nov. 17 due to holidays

Obama: Extend tax cuts for middle class, not the wealthy

President Obama said today his top priority is to extend the George W. Bush tax cuts for middle class Americans, and he will talk with Republicans next week about what to do with the tax rates for wealthier Americans."I continue to believe that extending permanently the upper-income tax cuts would be a mistake and that we can't afford it," Obama told reporters at the G-20 summit in Seoul, South Korea. "And my hope is, is that somewhere in between there we can find some sort of solution."
He added: "I'm not going to negotiate here in Seoul. My job is to negotiate back in Washington with Republican and Democratic leaders."

The tax cuts expire at the end of the year, and are the top priority of the lame duck Congress that meets next week.Obama said the Bush tax cuts should lapse for individuals who make more than $200,000 a year and couples who make more than $250,000.
Republicans, including incoming House Speaker John Boehner, R-Ohio, say no one's taxes should be increased in a bad economy, and that many wealthy people also create jobs.
Obama and aides have said they oppose a "permanent" extension of tax cuts for the wealthy, suggesting he may be open to a temporary extension.
That possibility has angered some of Obama's liberal supporters.
"The White House and congressional leaders need to say we are scheduling one vote, one vote only, and that vote is on renewing the middle class tax cuts," said Adam Green, co-founder, Progressive Change Campaign Committee. "And if Republicans want to oppose tax cuts for 98% of Americans, we dare them to and will pummel them politically if they do. That's how you fight and put Republicans on defense."
In Seoul, Obama said his top goal is "to make sure that taxes don't go up for middle-class families" next year, "not only because they need relief after having gone through a horrendous recession, but also because it would be bad for the economy."

Obama: Extend tax cuts for middle class, not the wealthy

President Obama said today his top priority is to extend the George W. Bush tax cuts for middle class Americans, and he will talk with Republicans next week about what to do with the tax rates for wealthier Americans."I continue to believe that extending permanently the upper-income tax cuts would be a mistake and that we can't afford it," Obama told reporters at the G-20 summit in Seoul, South Korea. "And my hope is, is that somewhere in between there we can find some sort of solution."
He added: "I'm not going to negotiate here in Seoul. My job is to negotiate back in Washington with Republican and Democratic leaders."

The tax cuts expire at the end of the year, and are the top priority of the lame duck Congress that meets next week.Obama said the Bush tax cuts should lapse for individuals who make more than $200,000 a year and couples who make more than $250,000.
Republicans, including incoming House Speaker John Boehner, R-Ohio, say no one's taxes should be increased in a bad economy, and that many wealthy people also create jobs.
Obama and aides have said they oppose a "permanent" extension of tax cuts for the wealthy, suggesting he may be open to a temporary extension.
That possibility has angered some of Obama's liberal supporters.
"The White House and congressional leaders need to say we are scheduling one vote, one vote only, and that vote is on renewing the middle class tax cuts," said Adam Green, co-founder, Progressive Change Campaign Committee. "And if Republicans want to oppose tax cuts for 98% of Americans, we dare them to and will pummel them politically if they do. That's how you fight and put Republicans on defense."
In Seoul, Obama said his top goal is "to make sure that taxes don't go up for middle-class families" next year, "not only because they need relief after having gone through a horrendous recession, but also because it would be bad for the economy."

Taliban, military attacks in deadly lockstep

Pakistan's reluctance to mount another major offensive against the Taliban may be due to its fear of equally deadly reprisals by the militants, which erode the government's credibility among its people, analysts say.

Last year, Pakistan launched two major offensives against militants linked to al Qaeda and Taliban in the northwest bordering Afghanistan and the United States has been pushing it to mount another one in their last bastion, North Waziristan.

North Waziristan is a major base for Afghan militants fighting Western forces across the border which critics say Pakistan sees as a bargaining chip for any eventual solution of the Afghan problem once U.S. troops leave.

But analysts say reprisal attacks by militants would be more lethal if the military goes into North Waziristan.

"There would definitely be more retaliation if they go into North Waziristan because the strongest militant groups are sitting there and this is also a factor of reluctance to launch operation there," security and political analyst Hasan Askari Rizvi said.

Violent reprisal attacks by militants have taken a heavy toll on civilian lives and they sap what scant support an alliance with the United States against Islamist militants exists in Pakistan.

More than 2,200 people have been killed in big militant attacks across Pakistan in the past three years and militants tend to intensify such attacks whenever the military mounts big offensives on their sanctuaries.

"Their retaliation is in proportion to the attacks and operations against them. If you are launching big operations against them, then they will launch big attacks," said Rahimullah Yusufzai, an expert on tribal and militant affairs.

Big military offensives in the northwest have almost halted after Pakistan deployed tens of thousands of troops for relief efforts during August's devastating floods, leading to a relative lull in militant attacks since then.

But a new bout of such attacks appears to have started in recent days.

At least 15 people were killed in a massive car bomb attack on the office of a police investigating agency in Karachi on Thursday while at least 71 people were killed in attacks on two mosques near the northwestern city of Peshawar last week.

The latest attacks came amid worries among militants that a fresh offensive in North Waziristan is imminent.

Hafiz Gul Bahadur, the main Taliban commander in North Waziristan, last month warned of an "endless war" if an operation was launched in his power base.

Pakistani officials say they will go into North Waziristan on their own timing, but they add an offensive in the region seems to have become inevitable.

Bomb stokes fears Islamists expanding in Pakistan

Pakistan on Friday accused Taliban and Al-Qaeda-linked bombers of attacking police in Karachi, stoking fears that Islamist networks are expanding their fight in the country's economic capital.

Gunmen rode up to the Crime Investigations Department (CID), used to detain terror suspects, on Thursday evening, exchanged fire with police and detonated a truck packed with explosives.

The attack killed up to 18 people and damaged the building in Karachi's most fortified downtown area, near government buildings, the US Consulate, five-star hotels frequented by Westerners and high-rise company offices.

Tehreek-e-Taliban Pakistan (TTP) swiftly claimed responsibility, with spokesman Azam Tariq telling AFP from an undisclosed location that the attack was to avenge "the arrest and torture" of his comrades.

But Interior Minister Rehman Malik blamed Lashkar-i-Jhangvi, the Al-Qaeda and Taliban-linked extremist group notorious for attacking Shiite Muslims and with its roots in the central province of Punjab, not the northwest.

"Lashkar-i-Jhangvi is behind the attack on CID building at Karachi," he told reporters in Islamabad on Friday.

Karachi police said that activists from Jhangvi and TTP had been rounded up in recent weeks.

"We detained at least 10 suspects from the bomb site and the nearby impoverished neighbourhoods," one security official told AFP.

"We think they have links with TTP and Lashkar-i-Jhangvi.

"We have arrested quite a large number of suspects in the last few months from Karachi and it shows that these groups have penetrated into the city. It seems as though these people have gained strength in Karachi."

The teeming city, with a population of 16 million, is politically tense and steeped in rivalries between the Urdu-speaking majority and an influx of ethnic Pashtuns from the northwest, which has been hit by Taliban insurgency.

But while outbreaks of political violence have killed more than 150 people this year and extremists have targeted Shiite and Sufi religious gatherings, attacks on government security forces in Karachi have been rare.

The significance is not to be underestimated. Karachi is Pakistan's economic hub, home to its stock exchange and lifeline for a depressed economy wilting under inflation and stagnating foreign investment.

It has further attracted attention from Islamist militants as the Arabian Sea port where NATO supplies dock to be trucked overland to support the more than 150,000 US-led troops fighting the Taliban in Afghanistan.

Pakistani analysts said militant organisations had regrouped and were capable of dragging government forces into urban guerrilla warfare.

"For the Pakistani state, it is going to be kind of urban guerrilla warfare if they want to eliminate these groups," said security analyst Hasan Askari.

"They're not in a position to overwhelm the state, but they are capable of sudden attacks and causing instability."

The United States frequently calls on Pakistan to step up the fight against extremists that it says are fuelling the war in Afghanistan.

Pakistan flatly denies US suggestions it is not doing enough to tackle Taliban and Al-Qaeda-linked militants who have carved out strongholds in the northwest and last year inched closer to the capital Islamabad.

According to Pakistani military statistics, 2,421 army and paramilitary soldiers were killed in fighting from 2002 until April this year.

Bombings across the country have killed more than 3,800 people since government troops stormed a radical mosque in Islamabad three years ago.

A Pakistani intelligence official told AFP there were two Jhangvi factions in Karachi, one allied to TTP that carries out bomb attacks and kidnappings, and another focused on killing Shiites.

"It seems as though TTP and its allied LJ group were involved in yesterday's attack," the official said.

"Some important security buildings in Karachi were their targets and this CID office had been receiving threats for quite some time."

Pakistan bomb shows militant reach

Islamist militants who attacked a police facility in the heart of Pakistan's largest city were attempting to free comrades they believed were detained there, a senior minister said Friday.

The coordinated assault late Thursday in Karachi, using a car bomb and guns far from Taliban and al-Qaida heartlands along the Afghan border, showed the ability of militants to strike back despite being hit by U.S. drone strikes and Pakistani army operations.

A gang of around six gunmen managed to penetrate a high-security area of Karachi that is home to the U.S Consulate, two luxury hotels and the offices of regional leaders. They opened fire on the offices of the Crime Investigation Department before detonating a huge car bomb that leveled the building and others nearby.

The police offices housed a detention facility that was believed to be holding criminals.

The CID takes the lead in hunting down terrorists in Karachi. Earlier this week, the agency arrested six members of Lashkar-e-Jhangvi, an al-Qaida linked group blamed for several high profile attacks in recent years. The suspects were presented before a court earlier Thursday.

"The terrorists were well prepared and they had came here to rescue their associates. But under a strategy, we had not kept those men at this building. So their plan failed," said Qaim Ali Shah, the chief minister of Sindh province, of which Karachi is the capital.

He did not say how he knew that the gang was attempting a rescue and not simply attacking the building, the type of strike that militants in Pakistan have often carried out in the past. Shah and other officials have not said whether the attackers escaped or where killed in the blast, which left a crater 10-feet (3-meter) wide in the floor.

Islamist militants are known to have found shelter among Karachi's 14 million people, and there have been occasional attacks on Shiite Muslims, whom al-Qaida and the Taliban believe to be infidels, as well a blast last month at a Sufi shrine.

But the city had largely escaped a wave of violence last year that saw many attacks in Lahore, Peshawar and other cities.

"These attacks which are happening around the country, they are carried out by enemies of the nation," said Karachi resident Faisal Mehmood. "It is not in Islam that you kill your brothers."

The government has declared war on the militants, and the army has moved into several areas in the northwest close to Afghanistan where the fighters are primarily based. The United States has increased the tempo of missile strikes in the region over the last two months, with close to 100 this year alone.

But the Pakistani state still distinguishes between militants who attack inside Pakistan and those who focus on fighting U.S. troops in Afghanistan or Indian rule in the disputed Kashmir region, believing the latter to be "good" militants. Critics say this policy is shortsighted, noting that groups are increasingly coalescing and support each other.

The Pakistani Taliban claimed responsibility for the attack, according to media reports. However, Interior Minister Rehman Malik said Lashkar-e-Jhangvi was the more likely culprit, or that it was working with the Taliban.

The Pakistani Taliban is allied with al-Qaida and has emerged as the most potent threat to the stability of the nuclear-armed country since 2007. Its suicide squads have killed thousands of people in attacks on government, security force and Western targets, most of them civilians, shaking faith in the civilian government.