An Aedes aegypti mosquito is photographed through a microscope at the Fiocruz institute in Recife, Pernambuco state, Brazil, in January. (Felipe Dana/Associated Press)

Ronald A. Klain was the White House Ebola response coordinator from 2014 to 2015.

The good news is that both the House and Senate have finally passed bills that would provide some funding to combat the Zika virus. The bad news is that this action comes more than three months after President Obama requested the aid. Moreover, the House bill provides only one-third of the response needed; pays for this limited, ineffective response by diverting money allocated to fight other infectious diseases; and necessitates a conference committee to resolve differences with the Senate bill, meaning we still do not know when any money will finally get through Congress to fund the response.

Of all the things that Congress could be truculent about, fighting an epidemic is the worst imaginable. Zika is not “coming” to the United States: It is already here. H undreds of people who caught the disease abroad are in the country; more than 250 cases of pregnant women in the United States and its territories with Zika have been logged by the Centers for Disease Control and Prevention. Soon, as summer arrives, the Aedes aegypti mosquito will become active in Southern states, and the disease will spread there. Cases of sexual transmission will take place as well. It is not a question of whether babies will be born in the United States with Zika-related microcephaly — it is a question of when and how many. For years to come, these children will be a visible, human reminder of the cost of absurd wrangling in Washington, of preventable suffering, of a failure of our political system to respond to the threat that infectious diseases pose.

Moreover, once local transmission of Zika begins in a few weeks, authorities will face the hard question of whether women living in such areas — here, in the United States — should be instructed to delay becoming pregnant, and whether those who are already pregnant should be relocated. Domestic travel warnings also loom. And still, Congress fritters away precious time on a dispute over funding that amounts to what the Defense Department spends every seven hours.

As befuddling as Congress’ refusal to approve funds for the Zika response is, perhaps even more of a mystery is why such approval is needed in the first place. If nature was threatening us with serious injury and evacuations via fire, flood or hurricane, the president could use his authority under the Stafford Disaster Relief and Emergency Assistance Act to provide immediate aid without waiting for Congress to act. The fact that epidemic “natural disasters” are the result of disease and not an earthquake or tornado should not constrain the federal government’s ability to provide a timely, comprehensive response.

Everything you ever wanted to know about the Zika virus and its spread across North and South America. (Daron Taylor,Claritza Jimenez/The Washington Post)

The man who led the effort to wipe out smallpox, Larry Brilliant, often says that the seemingly complex challenge of successful epidemic control can be summarized in one phrase: “early detection, early response.” Yet in the United States, the idea of “early response” is impaired by the absence of a public health emergency fund that the president can tap to respond to an epidemic. Slowness in getting the response to Ebola moving had devastating consequences in West Africa and led to panic and confusion here in the United States. Now, congressional delays on Zika funding risk a human cost of unknown dimensions.

If it seems like the world is being threatened by new infectious diseases with increasing frequency — H1N1 in 2009-2010, MERS in 2012, Ebola in 2014, Zika in 2016, yellow fever on the horizon for 2017 — that’s because it is. These are not random lightning strikes or a string of global bad luck. This growing threat is a result of human activity: human populations encroaching on, and having greater interaction with, habitats where animals spread these viruses; humans living more densely in cities where sickness spreads rapidly; humans traveling globally with increasing reach and speed; humans changing our climate and bringing disease-spreading insects to places where they have not lived previously. From now on, dangerous epidemics are going to be a regular fact of life. We can no longer accept surprise as an excuse for a response that is slow out of the gate.

Of course, we cannot combat epidemic threats with only a domestic response. Disease must be fought overseas to lessen the risk of transmission to the United States. We need to continue to press for World Health Organization reform, support the European Union proposal for a “white helmet” battalion to respond to epidemic crises as needed, and increase our investment in the Obama administration’s Global Health Security Agenda to help other nations build up their own disease-fighting capabilities. The House proposal to pay for the Zika response by cutting ongoing funding to these programs — funding approved by a bipartisan majority of both chambers during the Ebola crisis — is like sending all the firetrucks from one city to help fight a blaze in another: shortsighted and dangerous.

Here at home, we owe the American people an infectious-disease response effort as prompt, well-funded and effective as the Federal Emergency Management Agency (FEMA) at its best. We should create a Public Health Emergency Management Agency (PhEMA). And, whether it is housed in a new agency or put under the CDC or elsewhere in the Department of Health and Human Services, we should create a public health emergency fund that the president can draw down in the face of a dangerous epidemic — without waiting for Congress to act. The Zika-spreading mosquitoes are not going to wait to learn what a conference committee has decided on the Hill. Summer is coming, and Zika will be tagging along with it.